I've done a lot more reading since I posted this, and I think I'll put it to bed with this:
It's concealed if NOBODY can look at it and see that it's a pistol. If it SORTA looks like a weapon (outline), it's not concealed.If it's visible for just a second (shirt rides up), it's not concealed.
Fanny pack seems like a good combination except for accessibility. While a knowlegable LE or other gun owner can guess it's POSSIBLY a gun, it's still technically concealed, eliminating MWAG-concerned citizen calls:shock:, thus the disturbing of the peace rap. Of course, I guess LE might still want to check you out for your permit if they see the obvious (to them).
If I got this right, then thanks for letting me figure it out. If I'm off somewhere, constructive criticism is more than welcome!