2 pounds a week is pretty quick. It depends on what and why you are wanting to cut. If you are wanting long term leanness when the “cut” is over, I’d recommend going slower. Also you need to understand that progress isn’t linear. If you do something like cut carbs, you’ll drop some water weight quickly, but it isn’t fat loss. Don’t freak out and change things drastically every time you don’t exactly hit your target.
Do what’s easier. If you are really getting lean, you’ll have to pull all the levers at some point, but start by picking one, pulling it a little, wait till progress stalls, then up the ante. There is some evidence a higher amount of throughput (eat more, burn more) is probably better for body comp, but it’s marginal at best. What’s easiest for you to stick to is more important.
No, don’t do that…
I can’t speak intelligently about drug use like this because I’ve never used it, but that seems like a pretty big lever to pull when there is no reason to. If you’ve been bulking and have your calories pretty high, you should be able to lean out substantially without drugs.