I think that I've read about the leverage thing with wider bars is that if you're in the drops and you're like sprinting up a hill then the slightly wider bars will give you more leverage. Some say that wider bars "open up your chest" for better breathing and that smaller bars close your chest off. It's hard to say. If you're used to 38's then it might be fine OR you might be missing out on some great benefit (for you) of 36's.
I'll be interested in what you decide and how it works out. My shoulders are 40 and my Surly CC has 42 bars with the drops that slightly flare out. I've had the bike 3 weeks and have only tried the drops a couple of times.