Yeah, I've read/heard from several different sources that many folks will put bodyglide or vaseline on their feet to avoid blistering. I'd never tried it before yesterday, although in retrospect I really coulda used it last year on a self-supported trail ultra (lost half the skin on the bottom of my right foot...)

What I did was apply a liberal amount of vaseline to areas I'm prone to blistering in whilst wearing flats without socks. So at T2 all I had to do was kick off my bike shoes and helmet and slide into my flats, pull the elastic cord and then I was off and running in seconds. Worked great - give it a try sometime.