If you didn't already watch them, you should definitely check out the You Tube videos that I linked to in my post. One of them is a film of some seriously crazy adrenaline junkies running Crystal in an oar boat during a water release from Glen Canyon Dam, when the flow was increased from the normal 24,000 cfs up to 40,000 cfs. It's impressive! Here's that link again:
Running Crystal Rapid at 40,000 cfs!
Rick