Two things at once

The phrase two things at once appears twice in the basic set:
#B238 "Casting another spell does not break concentration, but you suffer a skill penalty for doing two things at once (see below)."
#*with a cumulative penalty of -3 or -1 depending on whether it requires focus.
#B366 "since you are trying to do two things at once, you are -2 on any rolls the GM requires to avoid falling, tripping over obstacles, etc"
Collectively this means it applies not just when "doing" two things, but even "trying" to do two things, simultaneously.
==Martial Arts==
MA107 expanded the Move and Attack guidelines:
:The GM should consider extending the -2 for “trying to do two things at once” to all success rolls except defense and resistance rolls against enemy attacks. For instance, it would modify DX rolls to evade or to keep someone from evading you, Fast-Draw rolls, rolls to stay standing after suffering knockbac, and Sense
rolls to notice something in combat.
==All-Out Attack: Double==
There strangely does not appear to be a -2 penalty when both attacks chosen are with a single weapon.
Even though this is effectively how a Rapid Strike at -6 differs from a Dual-Weapon Attack at -4.
==All-Out Defense: Double==
There is a "different defense" clause in Basic Set B366:
:Apply two different active defenses against the same attack.
:If you try a parry (armed or unarmed) with one hand and fail,
:a parry using the other hand does count as a “different defense.”
Martial Arts: Technical Grappling introduces "an exception" on pg 20:
:you may attempt two Sumo Wrestling or Wrestling parries (or two hands-free parries, pp. 22-23) against one attack, but the second is at -2.
*Hands-free parries count as a parry with BOTH arms, which would penalize a normal parry with either arm later in that turn by the usual -4.
The -2 in this case does not appear to be the "2 things" rule implied from B238/B366 though, but rather MA123 set Parrying with Two-Handed Weapons rule Multiple Parries "half the usual penalties for parrying more than once in a turn"
Those rules were initially just for weapons with reach 2 so Douglas Cole has extrapolated from them broader rules for using two hands to parry as a single defense.
*this may lead some to be curious if this should mean it should potentially apply to a Supported Parry (hand behind weapon) or Cross Parry (weapon behind weapon) but the difference here is that the implements are brought together at a single point: a Sumo or Wrestling parry does not necessarily represent that, but could have a gap between the hands
**it stands to reason though, assuming the arms are not held more than 1 yard apart on a Wrestling/Sumo parry, that this should be theoretically possible with Reach 1 weapon too
***Polearm/Spear/Staff/2H sword could be assumed to have an "adequate gap" between the hands to reduce the coordination penalty to -2, while there could be a "smaller gap" between the hands (shorter handles) of reach 1 weapons
****it is possible to move the hands further apart when fighting with a 2-handed reach 1 weapon with a small handle, MA111 says "moving one hand forward to “choke” the weapon or grip it by the ricasso." so to make Defensive Grip more attractive, this could be the only situation where GMs would allow using -2s instead of -4s.
==Discussion==
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*TBA
Category:Rules