really?
theres no way you can continually produce units off 4 gates?
maybe thats the case cus you eventually have to build pylons so you don't get supply blocked, then you'll have 100 less minerals to use on gateway units, rendering one of your gateways unusable for a short period of time. but that all depends on if you make the pylon at near-supply blocked supply, or making the pylon like 6-8 supply before you get supply blocked? it all depends on how you're doing with putting pressure on the opponent. you can usually just make a forward pylon and it'll serve as the proxy and normal pylon usage (making pylons for supply)
but i'm pretty sure if you diversify your gateway units... zealots/stalkers/sentries, then you'll manage your resources correctly. spending gas on sentries when you have little minerals and alot of gas, and stalkers when you have little gas and lotsa minerals, and zealots when you have minerals but no gas, etc.
2/3 gateway transitions are like the best build basically though.
4 gating sucks ****, i hate doing it. sucks that my once favorite matchup, (PVP) has basically been reduced to who can execute 4gate properly. my defensive 4 gate always wins :D i gotta keep the scouting probe alive though, to see if they try to contain me and expand. if they mess up ONCE though, i can force field my ramp and kill off some of their units, and then i can push out.