I only get trigger finger when I'm catching sharks. You have to be quicker with them than fish. You can't wait any longer than a second or else you miss them. Lol I'm always so antsy, sometimes I press too early xD
When I find myself with an itchy trigger finger I try to break the habit by casting a line at a few normal shadows and just letting the fish go without reacting to it in order to clear out that subconscious twitch.