I know you were referring to a QB, I'm saying the definition of a sack needs to be consistent. You were saying that since vick could have chosen to pass since a TE was on the line, it should be considered a sack.
My point is that, using that logic, any player who possess the ball behind the LOS technically has the option to pass. With the wildcat and it's bastardized forms, flea flickers ,option passes in the flat, etc. the qb isn't the only one who can pass.
On a reverse or any running play, a wr/rb could stop at any point, pull up and pass...but you assume it's a running play until the wr/rb actually DOES stop to pull up and pass...same thing with the vick example. Until he gets into some sort of a throwing motion, you have to assume it's a run, thus can't be considered a sack.
Stemming from the same argument, would you consider a 3rd and inches qb sneak that failed to be a sack?