I was recently diving at Roatan. On each of our dives, there were one or two other divers/dive masters/divemasters-in- training, diving along with us, specifically to hunt the lionfish. Our dive master still guided the dive, pointed out the sites, including lionfish, and the hunters took the lionfish. All of the fun divers found it to be a cool addition. However, had our dive master/guide, been completely focussed on being the hunter, I doubt we'd have thought it all that, perhaps necessary but not an addition to our enjoyment.