Is it always necessary to synch strokes between paddlers?
Absolutely! Synchronization is key to doing well in a double.
You can actually feel the boat jerk when you're slightly out of synch.
Rob
Currently Fenn Swordfish S, Epic V10 Double.
Previously: Think Evo II, Carbonology Zest, Fenn Swordfish, Epic V10, Fenn Elite, Red7 Surf70 Pro, Epic V10 Sport, Genius Blu, Kayak Centre Zeplin, Fenn Mako6, Custom Kayaks ICON, Brian's Kayaks Molokai, Brian's Kayaks Wedge and several others...