Heavy hooks/light leaders
It sounds to me as if you may have a somewhat unbalanced setup there. Don't know what sort of leader material you are using, but at 10/12lb test it's probably about .30-.32mm diameter, assuming you're using conventional nylon. Fluorocarbon/copolymer will be even finer.
I think 1/0 or 2/0 hooks just aren't going to fish properly on a leader this fine - it doesn't have the stiffness to present that weight of hook properly, and you may even find you have problems with breakages caused by excessive hinging. If I was using a 1/0 hook I would want at least .40mm diameter leader, and the same goes for heavy tubes.
If you need to use a fine leader, you'd be better to use a hook no bigger than size 4. Use a lightweight tube fly if you need a big pattern, or use a sinking leader/tip if it's depth you're after. I find that small hooks will land big fish at least as well as big; they tend to bury themselves right in to the bend, so you get virtually no leverage which is, I think, the main cause of losses. I have landed many large atlantic salmon on small hooks. You rarely see hooks over about size 4 used in the UK these days; above about 1" most people opt for tubes/waddingtons, or just a long, streamy dressing.