it would add more stress to the tranny because more than likely u will be holding in gear longer therefore more rpms and more heat but i think if u get a tranny cooler and temp guage and monitor it you should be fine. but i might try just runnin a wire the the autostick up pin and when driving in 2nd ill tap the wire to a ground and that should be the same as upshifting right?

Mods:
CAI, OBX exhaust, Grillcraft grills, altezzas, ard ryver g6 17's wrapped w/ falken's, VIS racing c.f hood, 2 12" kicker comp's w/pioneer h.u, streetglow blue undercars, red dash kit, indiglo guages, n other shit