When do we make the switch at QB?

[*rfaulk34*]

So...the indomitable Case Keenum, on 4th and 1, just pumped and reeled it back in, then threw a pass for a first down, because there was no passing lane (see: there was a defender right in front of him) on his initial attempt to pass. 

Just an observation. 

And then he fumbles...which doesn't negate what he did...