You're developing a nice body of work here, Eric. Highly speculative in some regards, but worthy nevertheless.
Your commentary on the placard-find really brings home to me the conundrum of the weather and the wind that night. We have such a wide range of testimony - Wind from the SW at 30 mph at 10K as the NWS says, versus 80 mph from the south at PDX, ala Capt. Bohan. Then add in the personal accounts of hellacious weather - the many folks at the 2011 conference who described a "Hellsapoppin'" night, along with Himmelsbach and Dona Elliot saying the rain was blowing sideways and such.
Bottom Line, I say, is that we keep looking at new areas until we actually find something.