I would agree that on a boat, where you have to get the fish completely out of the water and over the rail, a belly gaff on a big Halibut may not be the right choice. For yak fishing though, since all we need to do is control the fish, I recommend a belly gaff at any size California Halibut. They pretty much go limp except for their bite reflex (which I found out the hard way), and stay that way until you remove the gaff and lower them into the water. Not sure if this holds true for smaller fish or if you are trying to beat them senseless while on the gaff. I use a Boga type gripper on anything under 8# and only pop a gill for better bleeding on fish I intend to keep (but be prepared for some thrashing if you do this).
On that Hawaiian thing, does it matter if you use metric or standard rod? And what if the rod is standard and the fish is metric?
