Alright, guys, drop it.
I should have said: If you have GOOD hands, then riding in a shank bit WILL NOT HURT the horse, but you should get a snaffle as soon as possible.
That is the point I was trying to get across. I never said it was a good idea to ride direct-rein in a curb bit forever. The OP was wondering if it would hurt her horse - it won't, as long as she has good hands.
It's common sense, or at least I thought, that when introducing something that is a new sensation to the horse, to take it slow, and not just overload all at once. Whether it be taking up direct rein on ANY bit, switching to a shank for the first time, introducing side/draw reins, etc.
It was NOT my intention for the OP to think it was okay to start direct-reining on a shank bit without any transition period.
HOWEVER - to take up light contact and direct-rein WILL NOT hurt the horse, if you do it right and if you have good hands.
^That is what I thought the OP was asking.
Regarding the regular snaffles - I NEVER said I would prefer to direct-rein on a shank bit than a snaffle. I SUGGESTED to the OP that when she goes to buy a suitable bit, to look at double-jointed bits.
There were two SEPARATE conversations going on there.
Thank you, guys, for pounding this to death. I'm a bad person. Had one "bad" opinion. Let it go. I don't need 25 people responding with "OMG! Why would you say that? Bad!!! Shhhaaaaammmmeee!!!"
... besides, do any of you direct-rein with a mullen-mouth kimberwicke or pelham? It's not as big of a shank, but it's the same idea.
Please feel free to PM me if you would like to argue this point more, I would be happy to. Otherwise, for the love of Pete, let it die.