Depending on the specific type of layer (trial lawyer, defense attorney or prosecutor for instance), I don't think it possible to be a good at the job if ethics come into play.
Discussion
If it becomes obvious to the opposite though.. thats when you know you’re relying to heavily on bullshitting instead of the actual tool that you choose. Which is law not psychological warfare. It speaks volumes about character and what the person is actually after.
not defending it or making excuses, but that's just how it is. An ethical lawyer will never win a case and as such get no clients and go out of business. Paying clients expect results and they don't care how those results are achieved. Its baked into the system unfortunately