This has been my experience as well. I have a blueface angel that I need to relocate as it nips on certain corals. It unfortunately is smart enough to know that I want to relocate it.
Traps haven't worked, I've tried for more than two weeks. Placing six nets in the tank hasn't worked. The rock prohibits me from dividing the tank in half to make it easier.
I'm left with dismantling the rockwork. Should be fun.