Question: How are team members signaled when they should pull the rope together?
About the article "Tug of war", section "Tactics".

Candidate passages:
The day before The Pull itself, Pullers dig their pits into the ground to their own liking on the appropriate sides of the river.
Afterwords, the teams meet together for what is known as Rope Run, which is a sort of pep rally in preparation for Pull.
The pullers line up in the same order as their respective pits, alternating between paired freshman and sophomores.
The Rope Run can often get violent, as it puts opposed teams near one another at a time when emotions are running high.
Coaches and alumni have been known to swear and spit as Pullers and Moralers jog around campus with the rope, chanting "Even Year, Odd Year" in a rhythmic battle cry of sorts.
After Rope Run, each Pull Team gathers separately to do their respective chants and songs.
After all this, the rope is gathered once more, and driven to the site of Pull to soak in the Black River overnight before Pull.
Pull begins promptly at 3 pm.
Each team has 20 Pullers who each have their own Moralers, whom they choose on the same day that they are chosen for the Pull Team.
Moralers were once called "Morale Girls" but this was changed to allow more gender neutrality.
While there have been several female Pullers, there has never been a male Moraler.
As Pull is so physically and mentally straining, Moralers are important supporters in those respects.
However, their key purpose is to act as the Pullers' eyes as they cannot see the caller from their pits, and all 18 pits must move together for success.
Even Year and Odd Year each have their own, secretive methods for deciding the order in which Pullers may choose their Moralers.
At the beginning of the event, the rope is marked at the front of Pit 1, so that a winner may be determined should it remain very close and that a margin of victory can be measured.
While there are 20 pairs of Pullers and Moralers, there are only 18 pits.
Each team has what are called "sprinters" and "marathoners".
Pits 12 and 14 are reserved for these 8 special members of the team.
As the first half hour of Pull is both very crucial and very tiring, the sprinters are in these pits for that time.
At the half hour mark, both of these pits are switched and the marathoners go in for the remainder of the Pull.
There are doctors and judges on each side, and if it is deemed that someone must come off the rope (a rare occasion), a sprinter or marathoner may take his or her place.
Each side also has two more special pits, at the back of the team.
The very last Puller is the "anchor" and is typically the heaviest member of the team.
The anchor and his Moraler are the only members of the team who are standing for the entirety of Pull.
In front of the anchor is "pit 17" who will occasionally take on the anchor's duties while the anchor and his Moraler adjust the rope, and as such pit 17 and his or her Moraler must be specially trained.
When the losing team has lost so much rope that they must move their anchor forward to compensate, they then have 30 minutes to regain that pit.
If they do not do so, Pull is called, and the other team wins.
During this last half hour, each team removes the large banner that originally blocked the view of the other team.
Originally, the losing team was the team pulled into the river.
Since then, the format of Pull has changed and it has moved to a wider part of the river.
Tradition now has the winners climbing into the river and celebrating their victory as the losing team looks on from riverbank. 
Aside from the raw muscle power needed for tug of war, it is also a technical sport.
The cooperation or "rhythm" of team members play an equally important role in victory, if not more, than their physical strength.
To achieve this, a person called a "driver" is used to harmonize the team's joint traction power.
He moves up and down next to his team pulling on the rope, giving orders to them when to pull and when to rest (called "hanging").
If he spots the opponents tries to pull his team away, he gives a "hang" command, each member will dig into the grass with his/her boots and movement of the rope is limited.
When the opponents are played out, he shouts "pull" and rhythmically waves his hat or handkerchief for his team to pull together.
Slowly but surely, the other team is forced into surrender by a runaway pull.
Crevasse rescue is the process of retrieving a climber from a crevasse in a glacier.
Because of the frequency with which climbers break through the snow over a crevasse and fall in, crevasse rescue technique is a standard part of climbing education.
The basic assumption of crevasse rescue is that two or more climbers are tied together with a climbing rope, forming a rope team; a standard number is three, one on each end and one in the middle, which means there are two available to hold a falling climber, but is not as complicated to manage as large numbers of people attached to a single rope.
When the snow gives way under the victim, the others on the team must immediately prepare for the impending yanks, usually by flopping down and digging ice axes and knees (or boots if not wearing crampons) into the snow, facing away from the crevasse if possible, and holding tight until everything stops moving.
Many crevasses are small or slanted, and the fallen climber may be able to escape by digging or wiggling out; but if the climber is hanging in midair, one of several rescue techniques will need to be used.
The first step is to stabilize the situation and free up the climbers still outside the crevasse.
This can be done in several ways, typically involving one person anchoring the rope with a boot-axe belay, while the other person probes for the edge of the crevasse and attempts to communicate with the victim.
The main force technique is plausible when there are multiple rope teams; everybody simply hauls on the rope attached to the victim, drawing it over an axe shaft or other hard object so the rope friction does not cut a deep groove at the edge of the crevasse.
The Z-pulley technique is a moderately complicated arrangement using a small moving pulley to reduce the hauling effort.
The single-pulley technique entails dropping a pulley attached to another length of rope, which the victim clips to the climbing harness.
If the climber in the crevasse is able to move, he or she may be able to use prusik knots with slings or Jumars to ascend the rope.
The related bilgeri technique involves the use of a second rope, and prusik knots by the rescuers instead of the victim.
Once the victim reaches the lip of the crevasse, some combination of hauling and flailing will be needed to get over it, since the victim is still suspended by the waist, with feet still in the crevasse.
Although the mechanical principle of rescue is simple, the reality is far messier.
The victim may be injured and/or disoriented from the fall, the rescuers on the scene may be anxious or uncertain, equipment and ropes are scattered everywhere, and everybody will likely already be exhausted and out of breath because of the climbing and altitude.
It may also be that additional crevasses are nearby, and rescuers have died in unsuspected crevasses because they unroped in order to set up a rescue of the first victim.
The experience of world-class climbers Jim Wickwire and Chris Kerrebrock on Mount McKinley in 1981 shows how much can go wrong.
Only a two-person team, when Kerrebrock fell in, Wickwire was pulled in after.
Wickwire managed to get out of the crevasse, but Kerrebrock was jammed in the bottom, head down.
Wickwire tried to pull him out, but his shoulder had been dislocated, and he didn't have the strength; Kerrebrock eventually died of hypothermia, and Wickwire had to run the gauntlet of the remaining crevasses alone. 
Research has suggested that there are benefits to grouping gifted children together for the majority of the school day, which suggests that the limited meeting times and durations of gifted pull-out groups may have limited benefits for the gifted children.
A 1993 U.S. Government report found up to 72% of school districts using the pull-out approach despite this method being generally unsuccessful.
This lack of effectiveness has been echoed in more recent literature.
Likewise, Borland (2003) concludes that pull-out programming is generally unproductive.
Specifically, this is because pull-outs are composed of a hodge-podge of critical thinking, logic puzzles, and random subjects (like mythology) which are unlikely to result in any significant academic progress because they are not tied directly to the core curriculum.
Ironically, Winebrenner (2001) recommends those same ineffective practices, including creative problem solving, chess, logic puzzles, and academic competitions.
Oddly, Winebrenner also recommends that students selected for pull-out should be those who are capable in the areas the pull-out will address.
This is exactly the opposite of the approach recommended by most gifted literature, which argues for matching the instruction "to the student," not vice-versa.
Jan and Bob Davidson of the Davidson Institute for Talent Development criticize pull-outs in their book, "Genius Denied: How to Stop Wasting Our Brightest Young Minds."
On page 47, they say, "Most pull-out programs provide little beyond a creative outlet--and since districts that offer such programs claim they are helping gifted children when they aren't, they are often worse than no programs at all."
However, pull-out programs, when properly implemented, can be used to complement cluster grouping and other in-class differentiation. 
  Recognition - The party with the throw bag needs to see the swimmer and retrieve the throw bag  Preparation - Quickly the 'bagger' needs to play out about a meter of rope from the mouth of the bag, and try to get a partner to stand behind them holding onto them, preferably by the life jacket.
The bagger if they have time should take the meter of revealed rope and take it around their back so they can hold the tail of the rope, and the line feeding into the bag with their body in the loop, resting the rope on their back.
Communication - The 'bagger' needs to communicate to the swimmer that they are going to throw a rope, as the rope is best visible in the air, and can be lost by the swimmer when it is in the water.
Shouting "rope rope rope" is a common industry standard by rafting companies.
The Throw - The 'bagger' will grasp the meter of played out line in their off hand, and throw the bag either in an underhand or overhand fashion aiming to land the bag past the head of the swimmer, taking care to lead them as they will be moving downstream during the throw.
Anchoring - If the rope is caught by the swimmer the thrower has a very short time to anchor themselves.
This involves both them and their partner holding them from behind, sitting down, pushing off any rock or trees with their feet to keep from being dragged into the river.
If the bagger hasn't already they need to take the meter of rope around their back so they can hold onto the rope with both their left hand and their right hand, but have the weight of the swimmer be applied to the broad surface of their back, making gripping the rope easier.
The bagger or the swimmer should NOT wrap the rope around their hand, neck, or body.
Swimmer position - The swimmer upon handling the rope needs to turn onto their back with their head pointed upstream and the rope going over their shoulder as they hold it unwrapped in both hands.
The pendulum effect - On a straight river the swimmer will be naturally pushed by the current to the shore they have been bagged from.
When they get to shore the bagger can start to pull them in, hand over hand.