I need an english bit for my recently retrained OTTB mare. I've been using a tom thumb with a chin strap on her and she responded really well. She went from hard mouthed to soft mouthed after working with her. I tried a full cheek snaffle on her and she's a lot harder to stop now. I don't neccesarily want to use a harsher bit and I definitely don't want to use a twist. At first I thought I should try a copper roller d ring snaffle or maybe some kind of copper french link. But then I wondered if maybe I should try something with a chin strap, like a kimberwick. But are kimberwicks even allowed in the hunter ring? Or can I just attach a chin strap to whatever bit I choose?