Never heard of bottle conditioning at 75. I use a freezer with temp controller for fermenting in and would probably recommend a little cooler than 68. I usually set me freezer temp contoller at the low end of the yeast temp range ..... Usually 62-64.
As for bottle conditioning storage I have found that the cooler the bottles are stored the longer they seem to keep and the better they taste - long term.
As far as to what conditioning them at 75 for two weeks would do I cant say. But I have never had problem with them carbonating in my basement 58-68 depending on the season
Up next: Kolsch, Alpha Squirrel, Tripel rebrew, Witbier
Currently Fermenting: Charlie Sheen (barleywine)
Kegged: Tiger Blood IPA, Irish Red, Strict Observance Tripel
Bottled: Dry Stout, Pliny the ..... Squirrel?, Cream Ale