Execution is the most important thing out there, but you have to put your team in the position to execute properly, or even give the team an advantage.
For all of the talk of "execution is everything" then technically there would be no need to send players in motion, no reason to make audibles, no reason to make line adjustments, etc.
Furthermore by living by the "execution is everything" mantra, one could then reason that if it's 4th and 4, any team should be able to split 4 WR's and run a QB sneak against 10 players stacked in the box and get the first down if the execution is good. And it would be perfectly logical to line up a 250 linebacker up against Owens on a deep fade route.
It's like the one 2nd and short play where we ran the ball and Mathis stuffed it. We had run on 2nd down five times in a row and Mathis knew that we were going to run it again. Thus, he darted full bore towards the ball carrier and there was no way Glenn or any WR in the league was going to pick him up. In that instance, the predictability of the playcall made it extremely difficult for us to execute properly, unless Julius somehow eluded Mathis or if he breaks the tackle.
YAKUZA