R12 into a 134A system

[Mismost]

Got an AC buddy who will vac down the system and re-install R12 instead of 134A. I think in reading all the recent AC threads that is OK to do and in fact better as the system doesn't have to work at higher pressures.

Is this correct or was it just wishful thinking?

Part of me says go for it...the other part says don't mess with what ain't broke. Man, these cars will make you start talking to yourself!