If you think the most he will be is .740 OPS, fine, but I'd like to hear from you what factors you think will limit him from producing at his current level as a starter, especially since he's gone stretches of starting 6 out of 7 games and hasn't shown much signs of damage.
This is not a guy with a huge situational gap in his approach. He's a switch hitter and while he's having a little trouble batting lefty, it's not a fatal flaw -- he's hitting on his weak hand at the level you seem to believe he'll never hit any better than overall. Moreover, his BABIP as a lefty suggests that that number will go up -- if he gets it up into the ~.750 range, which is a rather modest improvement, then we revert to the .800 OPS standard even if his numbers against lefties (who he murders this year) do fall back a little as well. If that's the issue then you're majorly exaggerating the extent of the problem. His discipline is more than good, he's got at least strong doubles power, so if you want to project him as just a. 740 guy you're pretty much predicting that he'll be nursing a wrist injury every year like he was in 08 and 09.
you seem to be laboring under the misapprehension that I've given this no thought and that I'm reacting just because I like Jed. I do like Jed, and I'll defend him until he gives me a reason not to, but the fact is that you're way underselling the guy if you project him as just a .740 OPS player at the moment, because you're taking a rookie campaign and an injured year and assuming those, and not the numbers he's putting up now while healthy, are going to be the norm, which is frankly just a little ridiculous. Not that protecting a career of absolutely smooth sailing is any less ridiculous, but there's a middle ground here.
Besides, to be perfectly honest? .740 OPS still beats out Scutaro's .721, so even assuming everything you say is exactly true, you should still start Lowrie over Scutaro.