[QUOTE=alibi_18;8569545]
I don’t know why this part wasn’t included in my last post but anyway…
This sounds like a good plan. I’ve done it myself on a few horses and it worked wonders. It takes time but if you are skilled with 2 sets of reins, it will be easier to do the transition as you will be able to alternate from the bitless to the bit in the same ride and/or play with both at the time.
Good luck! :)[/QUOTE]
I was thinking along the same lines. I’d even say, if it’s an option, put your competition plans on hold for this season so there is no urge to rush things. Then ride bitless for a long stretch of time, months. Then put a very small bit in her mouth on the hangers, but keep riding on the bitless noseband. This first bit that you transition to doesn’t need to be your final bit, so it could be leather or rubber or anything, even if they aren’t “dressage legal.”
The reason for giving her a long break from the bit is that, IME, once a mare learns a reaction to something that annoys her, she will continue that reaction even if the annoying thing is removed. So right now, she may over-react to any bit even if it isn’t bothering her that much. The same way that a mare can learn to toss her head from one or two rides with a clumsy beginner, and then continue tossing even when someone more skilled is riding. OK, maybe not just mares, but mares in particular. So she may need time to forget that a bit ever bothered her, before you try out potentially more comfy bits.
While you are riding bitless, see if she throws any resistances at you, if there is anything that pops up to replace the bit chewing. That will help you see if the bit discomfort is the central problem.
However, riding bitless, there isn’t really a way to have meaningful contact like there is in a snaffle, which is both a problem and an opportunity. It means that you will end up working a lot more on seat, leg, balance aids. It also means that if you are at all “handsy,” you can cure that because you will be riding more on a slightly draped rein.
When you start to introduce the bit again, you might want to do some of the in-hand work like you would do with a colt, to re-introduce her to the bit. I think you said in your OP that the mare goes nicely in self-carriage with little contact? Or did I get that wrong? Anyhow, it is possible that she has never really learned to accept contact, and even when she seems to be going with a correct posture, is actually behind the bit to some extent. If that is the case, teaching her to seek contact and reach for the bit (rather than just put up with you taking contact) might help.
I worked through a set of problems on my mare a few years ago by switching to a sidepull (basically, just a noseband) for about a year, to my coach’s horror :). Maresy would still stretch to the bit, and I found she would still collect (to the extent we’d reached with the snaffle at that point) mostly with me shifting weight. But over time, we lost some of our bend and balance. There just wasn’t quite the nuance of communication with no bit. We got it back quickly when I returned to the snaffle.