I thought it was pretty far fetched also, especially the 5 second deal, not to mention that Hummer outrunning the explosion. Hell, it would probably run outta gas before it got clear of the building anyway. Very Walker, Texas Rangerish.
But to be honest, Caruso is so badass, that if they had him fly around the Earth at superspeed to reverse time, then swoop down and save the guy while holding the building together with his mind, I would probably still be back for more next week
but I sure do miss Speedle