I think it's more of an instictive feeding trigger behavior that I saw. As most older members know, I used to run a TON of current in my tanks, something like 10,000 gph in a 150. The goonch and atf loved it. The goonch parked itself on some rocks in the strongest, most violent part of the current. When one of the other fish would let the current push it past the goonch, the cat would sometimes dart out and sometimes bite. It would never finish the attack when the prey item was large. A few other fish lost the lower lobe of their caudal fin this way.
Just an observation. If you're not running the same hurricane wind in your tank that I was, you might not be able to trigger this behavior. Worth noting either way.