Isn't that basically what we have now in sudden death OT? I think this might be on the horizon. For instance, at the end of the third period, the QB's gather on the 50 yd line and they have to hit pie plates off a pylon on the goal line.
I still maintain that the games should be much shorter and get rid of all the repetetive "runs up the middle" and the "12 yard out patterns that usually miss". Condense the games into short, exciting 10-15 minute thrusts of energy and let the boring plays fall by the wayside. More excitement, more commercials and analysis, more rest between plays (2 mins mandatory or penalty if you try to put the ball in play before 2 mins). This all equates to player safety and longevity.
Your premises is flawed. Just because the game is shortened to three 10 minute periods or two 20 minute halves, the play clock is expanded to 2 minutes in between plays. So Rex and Rob have plenty of time to discuss the plays and can review an assortment of comments (on TV, Facebook, Twitter and via text messages). All of those things would be permitted so they can make the best decision during the 2 minute play clock. I don't see how they would feel rushed. Maybe it's the overwhelming negativity most feel about Rex and Rob but I think they would Excel in this type of program. Go Bills!!