I think it is more a case of I hesitate to run a treble off the tail rather than I prefer the single. For pure fishing purposes, I like the treble off the back. The reason I don't use it is because of the damage I've seen a trailing treble do to the fish. That said, I've also seen the trailing single hook do a bit of damage as well but I've seen more damage done by the trailing treble over time.
I find this combination gives me what I am looking for. Singles hold fish better once hooked than trebles in my opinion but trebles hook more fish. To me the ideal way to attach hooks is via assist cord as it makes it harder for the hook to twist out but it is such a pain. I quite like using two split rings on the single hook on the tail.
You'll find different people have very polarised views. The guides on Nomad are completely anti-treble and anytime you drop a fish if you have a treble hook on your lure, it will be because you're using a treble hook. That said, noone seems to say anything when I drop a fish using a single off the tail and a baker off the belly! On the other hand, the boys at Le Poisson Banane are absolute treble hook users. I think it really is a case of using what you are used to and trust.
I had a guide recently basically tell me that my experience over what is approaching nearly a decade of GT fishing with trebles counted for nothing because he did it for a living so he knew better. I treated that comment as it deserved - I think I might have been on the end of enough GTs to know what works for me. The big issue with trebles is that you really need to ensure you work hard to keep the tension on.
Ray, I don't usually use ST-66s because they're too easily compromised by decent sized fish and I don't like Jobu's because they're too long in the shank. I tend to use ST-76s and Decoys. For my singles, my preferred hook are the Fisherman Shiden 13/0, the Owner SJ-51 11/0 and the Shout Kudako 7/0. These are all jigging hooks with shorter shanks. I appreciate that sometimes, ST-66s are ideal because of the size of the poppers but if this case, I'd suggest you think about a baker rig. The baker rig is a very good rig for the belly.
While there is no doubt great benefit in looking at how different people rig, I'd encourage you to experiment till you're comfortable you've found what works for you.