[aztecx]

I haven't watched the replay nor know if the build you are trying to use actually works but I have my doubts. Generally you either tech or you expand. It's very hard to saturate and stay on top of minerals when you've just created a lot of army units + expanded + made a second gas. I would suggest maybe sticking on 1 gas till your bases are saturated and just tech whenever u have obtained 100 gas from that single gas. Once your bases are saturated and you have teched/started teching it is easy to drop a 2nd, 3rd and maybe even 4th gas to accomodate any tier 2 units or upgrades you wish to make.