Rick, I think they are a fine clamp. Like I said before, they are just a royal PITA to use, esp if some retard slid the clamp around so you cant get anything on the tangs to loose it (esp if the hose is vulcanized).
I think your logic (to me) is sound - they should work great. I just dont know where to get them. I would sorta think with as small a Coefficient of expansion as most metal has, that the supple rubber would make up for the difference (regarding the leak issue).
As an aside, I think I have seen (online) a band clamp for hoses, which looks cool (sort of like an exhaust band clamp, which is also a cool idea). But it would not eat into the hose and might seal more uniformly.
Good luck bud.