Well I only started shooting topside seriously this year. I usually shoot video which is difficult to keep steady vs shooting film(motion pictures! not still) in a small boat with choppy water. U/w I'm still video exclusively due to the fact I think the strobes disrupt the feeding when too many people are around and I like getting the movement of the baitball more than anything else.
I do know baitballs like the one where Doug's winning shot was taken, with the right viz and the sharks in super frenzy are rare. He was also with a minimum 300 sharks in the water and knocked silly by the blacktip and dusky sharks. And the best stuff came from that one day. And it was taken by Doug Perrine. It's one thing to take pics for coral heads and nudibranchs. Super predation shots take it to another level and there aren't too many guys of Doug's caliber, at least not so many I've seen.
I know many of the brits who come down... Tony White and his crew esp. Unfortunately there are many factors besides having the right baitballs in the right viz. One of them is overcrowding. Predators like dolphins and sharks get spooked by divers, so experience in handling baitballs and basically not overcrowding it is very important. This year esp baitballs broke up even when the boat approached.
Topside shooting is definitely easier since those elements are easier to find and see. Can't really screw up shots of gannets when there are 10k of them. Or common dolphins when there are at least 2k of them. But the holy grail is the baitball. But I just love the experience...and hope the Wetpixel guys going have almost as much fun as I have every year.