the gas management is pretty simple and reading the right articles will cover most of it if his normal tech training was done properly.
For the UTD system specifically you have to turn one bottle off. The frequency that this occurs is up to the individual diver and also the size of the tanks. Larger tanks have a larger buoyancy swing/psi used, so on big steels a 300psi difference might be enough to notice, on smaller tanks you might not have an issue with a 1200psi swing. One of the common methods in cave country is 600psi left, 1200psi right, 1200psi left, etc. We use 600psi because a 3600psi fill is "full". Doesn't matter whether or not you are using the UTD manifold or swapping regs, same principal. I'm not going to waste my time watching the videos again, but I'm 99% sure that in at least one if not more of the videos he mentions turning one tank off.
This all being said, UTD wants you to get trained, though with there comical advertising at DEMA saying they needed instructors I'm not sure how many sidemount divers are actually buying into that ridiculous system. They aren't going to go out and tell you exactly how to dive their system because they want you to take their class which is more money in their pocket. You're going to have to hunt pretty hard to find one. There is one on the east coast, she is in MD. She is literally the only one in the country that isn't in California. Tanya Kuck btw, never heard of her, and due to lack of mutual friends on FB I'm assuming she's not a well known cave or tech diver either.... Not saying she's a bad instructor, just that I'd be skeptical, this end of the community is pretty small...
The videos AG has posted are pretty good, watch them all at least once if not more, and make sure you pay attention to them, that will get you most of the way there. After that you'll have to either go to MD or CA to get trained on it because I don't think any of the instructors in NFL will touch that system with a 39.5' pole. They're accommodating on different bc's, but I've never one of those systems used down there and the one person that I saw that had one, was using the "normal" sidemount setup after his first dive.
