Hi and thanks for your comments. It isnt a lake so I get out in the bigger waves from time to time. I havent had any problems so far with this but I really appreciate your concern about the frame etc. Is there any way one can test this on land,,, I mean to see if there is any problems?
I've raced 17s for 16 years and I know the boats pretty well. I own one of the last ones built (2007). I'm an engineer and a naval architect. Contrary to fastcat's assertion, I don't really care what people do to their boats - as long as they're doing it for fun and not racing.
I've broken both front and rear crossbars - with just the standard 17 rig. I know of a lot of other people (racers) that have had the same problem. Hobie Cat Co. ended up installing stiffener plates inside the crossbars sometime in the late 80s / early 90s to prevent breakage. (The crossbars crack on the bottom, starting from the bolt hole.)
I see the frame twisting at about 1:25 in the video. Every time you pump the main, the rear corner lifts up.
There's no real way to test whether the frame is up to the stress. If it goes, you'll hear a loud "pop" and the frame will get very loose.
The real problem is - there are no new crossbars available as replacements. You'll need to find used ones if you break one.