I have seen very little problem with hooks up to 1/0's or 1 1/2's in Alec's hooks but 3/0 hooks can cause damage to smaller steelhead...

If you would like to tie up some larger rabbits, tie them on tubes where you can vary the length of your fly while still fishing a size 4 up to a 1/0 hook...plus with tube flies you get a much better hook:land ratio then with flies tied on standard hooks.
Ryan S. Petzold
aka Sparkey and/or Special