To the thread creator quit birching and just try on 12 and 13's. I have worked in a shoe stores for the last 9 years and people like you piss me off. EVERYSHOE FITS DIFFERENTLY. Nobody has a closet full of shoes that are the same size. i own everything from a 10 to a 12.
And to the person i quoted, a half size equates to 1/6"
12.5 is nothing. I've fit a lot of people for ski boots who wear that size shoe...
Last year I had to custom order, and fit a size 16 ski boot though... I had to order custom superfeet for the dude, and all this other shit..
actually you'd be surpised how many girls look at feet and hand size for that estimate.
Don't feel to bad.