^Kirk was promoted from captain to admiral prior to TMP and again prior to TWOK. But it's generally accepted that he was a rear admiral, which in the US Navy was the equivalent of the commodore rank once that rank was phased out -- i.e. just one step up from captain rather than two.
Haha, wow… I think I did actually consider that, but somehow felt it wasn't valid because "commodore" was being phased out or something... I dunno. Clearly it was past my bedtime!
But yeah, Archer seems to be giving Kirk a run for his money in the department of Freaking Awesome™, so similarities in rank history would not surprise me.