I've always know it as a tear drop shank snaffle which, of course, will make people scream "it isn't a snaffle because it has shanks!"
Semantics aside, we used it to transition our western colts from the true snaffle to a shanked bit. We'd start with no curb strap, just to get the colt acclimated to some poll pressure and the low-leverage curved shank. After a ride or two, we'd add a the curb strap to the same ring as the headstall and then let the colt get acclimated to the new jaw pressure. The horse should already mostly know how to neckrein by this time, but this was considered to be milder than a longer shanked curb if we did need to take a hold of him during training.
Last edited by Cynical25; 08-01-2013 at 11:09 AM.