I ride a 15 year old, Thoroughbred mare named Sassy. I show in halter, Western Pleasure Classes, English Pleasure Classes, Trail, and Games. She places in the top of every one.
For Western I ride in a Low Port Copper Curb, my friend told me the mouthpiece is a 'Mullen Mouth'? Its a low port, but it is extremely wide, I think 3" wide. She works really good in it. I worked her in that a lot, and she is really loose in that, but you aren't supposed to ride 2 handed in it, which... ya I do (don't kill me for it). The judge at a show really liked her and said I should put her in a snaffle and really work on collection. For training I put her in a O-ring snaffle with a plain mouthpiece. I used to game with her in a D-ring roller snaffle.
She is really flexible left/right and bending at the poll at a WALK and STANDING. *Please don't say work on loosening up at the walk, she is really loose*. Our stop at a walk needs work, but from today she has improved a lot. When we go up into a trot she is a bit loose but gets pretty tight. If I pull back and squeeze my calves and will loosen up for a while then get tight again, and we don't really have a stop. Our canter... Right now I've been cantering her in circles, she does get tight and we haven't work at all on the cue with looseing/head down. But stopping... ya it can be a struggle. Backing up she gets a bit tight also and resists.
In her pleasure bit we DON'T have these problems.
I'm constantly flexing with her, which she is really good at. We do turns on the forehand and hindquarters, sidepassing, etc...
In english I show in a Kimberwick, which she works really good in.
I don't know if I should work in the D-ring snaffle or try a different one but we just are not getting anywhere.