Indeed they might get wise to the option play. What they can't do is catch him. He is a gazelle.
Right now you can see the confusion even from the Ravens on option plays but more often than not the QB takes a lick and a serious one. Legal by the way, the hits will more and more purposeful since they are entirely legal. Defenses will gladly sacrifice yards vs putting a QB out of the game or the season. That is the main purpose of the offensive line, protecting the QB, once out ... He'll likely outrun most middle linebackers in the NFL but when you start putting hulking safeties like the Seahawks' Kam Chancellor at 6'3", strong, fast and a very hard hitter, the outcome changes: He'll be hit a lot more even when he doesn't run the ball in an option play, they will rush with more abandon and make sure they hit all the options. Fortunately he's not a one trick pony and that was my point: he's deadly accurate, maybe as accurate as RGIII just maybe, people seem to not notice how accurate RGIII is, and has a strong arm. These guys feet remain a weapon but to be used more scarcely thus they would last longer.