Herb,
regarding damaging fish and trebles, and I know a lot of folks are gonna want to smack me for this, but this is mr personally experience...
Big Barbless Trebles cause little to no more damage to big fish than big barbless singles... and less damage than barbed singles in my opinion... I am a big fan of large high quality Barbless treble hooks unlike a lot of folks... I use them on large GT lures a lot... because in my opinion, on a fish as brutal as a GT, they do the same damage as a set of singles.... and they do help a lot of lures swim beautifully..
On smaller lures/fish with smaller trebles I find they do VASTLY more damage, and I am not a fan of trebles of any kind in the smaller sizes...
Only place I would use trebles under 5/0 in size would be on lures cast for Yellowfin where the intent is to keep the fish....
I'm all for the protection of fish, and doing everything I can to improve their chance of survival after I've had my fun with them... and in my opinion the best way to do this is to crimp/flatten your barbs... If I think a Treble hook is a better weapon to be using on a certain lure, I will most definitely use it, but will always flatten the barb...