I'm pretty sure the time difference in that craft, undergoing that sort of acceleration, between Mach 1 and Mach 1.4 (as I've heard from a few sources is when they planned to activate feathering) is pretty short. Arming the feathering controls at that point could have been perfectly standard procedure if you're expecting to use them in a short few seconds.
I think this is probably just a tragic mechanical failure - as terribly as that may be, my thoughts and condolences to the family.
On the other hand.. one man surviving a breakup of a mach 1, rocket propelled, plane at 50,000 feet without an ejector seat and (so is told) two seconds notice?.. Buy that man a Beer.. and another 10..