I have to agree on mid-wide as well. Size 11 boots are kind of in the "nice zone" of
being able to ride all 3, depending on your stance and riding style.
Its kind of a nasty little formula when you factor stance in. By the books, I'd lean
on mid-wide at the narrowest. That way you can ride narrow, or wide in your stance
and not have a big amount of toe/heel drag. Then again if you know you ride a wide
stance, you might be able to get away with riding a regular (over all board length will
also effect this). Best way to test this theory is, pick the board length that you want.
If you've been riding long enough to link turns and enjoy riding, you probably have a
good idea of your ideal board length, no matter what a size calculator tells you. Rent
one from the rental shop and ride your natural stance. What really feels comfortable.
If you feel your toes or heels drag, or if it looks like you have severe toe/heel drag
(boots hanging way over both sides of the board), then step up!
Testing is always better than regretting. Everyones riding style is different, which
makes it hard to completely dial it in. But by the natural law of snowboarding
facts, yes. A mid-wide is the way to go. Now its up to you to see if that is true or not.
Good luck! Do some tests, and get back to us! We'll get this solved somehow bro!