Greenland kayaks were developed by the Inuit to use to hunt... They'd go out to kill seals with them in freezing water temperatures doing open water ocean crossings and dealing with the surf. And they carried the seals they killed home on the decks of their kayaks. A kayak that is unstable enough that it rolls easily in those temperatures is suicide & their families wouldn't get food... It's a design that's been tested by thousands of years. The inuit did train their sense of balance using greenland ropes and could do a ton of different types of rolls...

So yes, greenland kayaks are easily rolled if you want to roll. If you don't want to roll, generally they don't... If you watch someone who does know a lot of greenland rolls, it's like watching water ballet... Alison lives around here & is just beautiful to watch and I'm pretty sure that her accidently rolling over her boat hardly ever happens.
http://www.youtube.com/watch?v=vN4QrNVbnv8

Most kayaks now a days are greenland derived. Some people still make classic greenland skin on frames... And the sea kayaks are all compromises... racing boats will go very fast in a straight line & be hard to turn - so people put rudders on them to make them easy to turn. Greenland kayaks will be more maneuverable, but will sacrifice speed... Other boards are made to be surf/rough water condition kayaks...


I'd call greenland kayaks stable... But then I've got a 19" wide surf ski that has absolutely no primary stability and I absolutely cannot relax in (yet)... But if you watch big ocean surf ski races... There are all sorts of people that race surf skis out in the surf & ocean without flipping. Try getting in a k1 racing kayak sometime... and those are unstable. But people learn to paddle them without having to brace constantly.

From a whitewater background, I'm sure you know that boats can flip in response to conditions, that's why white water kayakers learn combat rolls. And that's why you learn to brace and how to read the water currents. And depending on the design of the white water boat, how easy it is to roll or do tricks varies... And even in a canoe - there are some things you don't do... standing up in your canoe is probably a good way to flip it over.

Most of the time, it is hard to actually flip a sea kayak. If you ever get in one, spend some time wiggling your hips back and forth (or lifting your knee up on either side) - almost all of them have pretty good secondary stability - you can lean them without flipping and you're meant to do that to steer them. I can probably count on two hands the number of times that I've flipped a sea kayak in the 5 years that I've been kayaking... A couple of times were because I leaned way over to do something stupid, but most of the times were because I took the kayak out into breaking waves on the beach to play... repeatedly. That's just been a really fun learning curve - but I roll over, I roll back up. Not a biggie.

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