I'd love to see some Tebow Zone reads out there, although I have noticed him make the wrong read a lot on that play since being in the NFL. Plus Tebow can extend plays like Big Ben, which doesn't have a high success rate, but when it does its a huge play. You can win games with big plays. Live by the three die by the three kinda thing.
Not that the vertical threat wouldn't help, but the 'purpose' of the spread is to create space horizontally, not vertically.