There are different versions
What is called a back deck roll varies by kind of boat and history. The standard for WW kayakers, especially playboaters, seems to have shifted to the keep-your-head-dry version. You can see that demonstrated here:
http://www.boatertalk.com/skills.php?id=126
You can also see from those pictures that the orientation of Ken Whiting’s blade is crucial and how the feather of the inboard blade makes a difference. The video in your posting shows a very different technique. Since a waveski is much easier to rotate than a playboat it can be righted with just a hip flick with some paddle support. There is no sweep as there is in the Whiting pictures. So, it seems to me that you should be able to roll the waveski with any paddle, no matter what the offset, since there is no trailing blade to worry about.
good point.
I went back and viewed the waveski video a couple more times and it seems that the trailing blade is in the air when rolling so there wouldn’t be drag in the water. Heck that roll looks more like a C-to-C with an extreme layback than what I would consider a backdeck roll. I guess for that roll, I stand corrected in that offset wouldn’t matter.
As for the head dry playboating backdeck roll, my timing still isn’t right to keep my entire head out of the water. I can keep my hair and eyes out of the water but I’m still drinking water. After taking Tyler Curtis’ class, I had major roll envy. I want to be able to backdeck roll while talking to people! 
Disagree On Small Point
my white water boats are, in my opinion, way easier to roll than my waveskis.
sing
That’s interesting.
I think I could roll my Dom 47 like he does in the video. I will give it a try in the pool session on Monday. But I am sure I couldn’t roll my Dragorossi Fish or my Riot Disco that way. Unfortunately I don’t own a waveski to try. If waveskis are more difficult to roll then I wonder about the advisability of using the technique shown in the video.
Much More Abrupt…
the white water boats have sidewalls/chines that help in transitioning the rotation. Even surf kayaks have a bit of a side wall, in addition to the rails. Waveskis just have the rails and a small hump on the back. It wants to sit flat right side up, or upside down. No transition point. You have to defeat the rail and high primary stability with a good footsnap (on the stirup akin to hip snap on the thigh brace).
Sometimes if you don't good hipsanp in a white water boat, you can still get on the side and finish the rest of the way with a scull or two. No can do with the waveski. You do a good roll or you don't come up. No trying to save it with a scull because there is no mid rotation point.
sing
as well …
this all seems pretty confusing…
sing: what roll do you use in your waveski and are you pretty much bombproof w/ it in the surf?
Sing’s roll
Having seen Sing roll his waveski in some pretty big conditions, I can vouch for his ability. By far one of the best rollers I have ever seen. He has the skills and I’m sure will answer your question well.
Tim
I Use A Regular Sweep…
and occaisonally a back deck roll. I use the back deck if I bury my face early on in a ride and want to come back up still riding the same wave. Otherwise, I just go to regular sweep roll, more with a layback finish.
I just started waveskiing at the beginning of the summer. Once I figured out to pull up on the footstrap as the hipsnap equivilent, I have become pretty bombproof. Last time I pull the buckle was several weeks ago when I was up against the shore and getting hit with a bunch of short interval waves. I just decided to bag it since I wanted to take a break, pulled the buckle, walked about 10 paces onto dry land. Two days ago, I was surfing on my own. No way was I going to bail and swim on my own in deeper water.
sing
LOL!
I never blow a roll in big conditions with the waveski. My secret... DON'T GO OUT THERE! YIKES!
As I posted somewhere, 5-6' is the max for my confidence factor on the waveski. After that, I need to be in a decked surf kayak. I feel much safer. It's like being partially back in the womb. :)
sing
Come On! : )
Don’t be modest. You have skills!
Tim
Don Beale Greenland paddle
Get a Beale Greenland paddle and practice the basic layback roll and all this debate will be unnecessary. Any other Greenland paddle will work also.
Dave
Likely Unworkable…
he is a waveskier. I highly doubt he would use a GP for his waveskiing. Heck, I am a dedicated GP user in a long boat. But, I wouldn’t touch a GP my white water and surfing boats and waveskis. It’s not the optimal tool for the job.
sing
wrong tool, wrong roll
I own two Beale paddles and am an avid Greenland paddler/roller but there is no way that I would ever consider taking a waveski out to surf with a Greenland paddle. It is simply not suited for that type of boat and paddling. Also there is a fairly large difference between doing a standard layback roll in a sea kayak and doing a back deck roll in a waveski or a playboat. There isn’t one roll which is best for all conditions/environments and discussions like this one are a great way to get a better understanding of the various options out there.
Dave, I’m not sure what your intentions were with the post and I may be reading too much into it, but there is a hint of dogmatic closemindedness in what you wrote that I find slightly distasteful.
alex
You ever roll a waveski?
Mine is about 100 times harder to roll than my Jive.
More like trying to flip a piece of plywood.
I watched a Level 5 BCU instructor try about 5 times before he got it over.
Note added after posting .... reading the rest of the thread I see Brother Sing has set you straight. I have found using an extended paddle and almost dislocating my arm is an effective way to flip my ski if all else fails.
apology for ignorant post
My old brain read the thread quickly, didn’t focus on “Waveski” which was the critical qualifier, and gave an ignorant response. Sing, Alex and Seadart, you all were too diplomatic to my imnorant post- I deserved worse. Will try to read posts better before responding.
Dave