These big blocks can attract high-flying, distant ducks of both puddle and diver species. Keep some separation between the last diver deke and the first of your puddle duck blocks and continue to position the last puddle duck decoy no farther than 35 yards from the shooters. If Canada geese are in the area, and legal to hunt, use more. Keep the goose decoys separate from the ducks. The type and numbers of ducks you see, and how they behave, will help determine that.
Alarmed ducks tend to group up before they flush.
Even with all the work required to set a big spread, this is critical to success. Have the most experienced caller in the blind do the main calling, with other hunters using only low guttural feeding chuckles. The late season is especially challenging, not only because of the often brutal weather, but because most ducks have become educated to hunters and their tricks. By now, many ducks are shy of calls and decoy spreads. Some of the most successful waterfowlers pick secluded spots they haven't hunted, set out a half-dozen decoys and simply wait without calling.