I have never done it with a modern commercial dive operator, but did it unofficially many times in the past with some local commercial fishing boat operators who "sidelined" taking out divers. It was a real rough and ready affair and you had to endure your gear reeking of dead fish for a few days as everything was stored down in the hold, (fish, gear, bags, anything...) but at the time, thats all there was, so we took it.They were also pretty much done on a day basis, but the boats launched all over the place up and down the coastal beach's so they could get to the shoals as quick as possible, because, believe it or not, they move at a fair clip. Although now its a much more civilized and planned affair, the basics remain the same.True, conditions can be tough, both on the boat
and sea conditions,... its generally done as a blue dive too (no bottom in sight) so buoyancy control is also important and in the rough conditions often experienced it can play a part, but.......all things told its a great experience if you can do it. I understand the shoals are getting smaller and smaller and staying further and further out to sea....so who knows how long it will continue, so if you get the opportunity its worth doing now.