I'll take whatever Coach wants to do with a smile. If the game shakes out that no "right" QB is available, then our roster situation says we can defer this time. The difference between "just taking someone" at QB and having another scholarship for an elite athlete somewhere else [even saved for next year] is a no brainer to me, and I assume that Kelly would manage that way too.
That scenario requires however that our QB situation remains "status quo" numbers-wise. Kelly has to be at least considering the following possibilities: a). Crist gets hurt again and/or leaves after this season; b). Hendrix thinks that Golson is passing him up [could go the other way, but I feel that this option would be more likely] and with some regret decides to transfer; c). Kelly considers a season with just two active QBs [say, Golson and Rees], winces a little, and goes the conservative route.
Admittedly, it seems like a longshot, but it's certainly not impossible. Good managers think worst-case-scenarios all the time. When such a scenario applies to the overwhelmingly critical functionality of ones system [i.e. QB play], you may well not want to roll any dice at all.
P.S. while I was typing that, the next poster said essentially the same thing --- sorry for the duplication of thought.