The issue is that sometimes Lisa will play with the (usually left) shank of her bit and get it between her lips or between her teeth - new version of getting the bit between the teeth :)
It doesn't seem to me to be anything more than just playing, but it's annoying and what if she ever figured out that if she held on to it that I wouldn't have the command control that I usually have? Today once when I flipped the rein to get her to drop the shank (jeeze that sounds weird), instead I had to give it a little pull and I heard it grate against her teeth. Eek - it gave me shivers hearing that.
She's a good solid quiet horse. This never appears to me to be anything tied to pain, not wanting to do something or go somewhere. Just fiddling. She'll do it riding or standing mounted or just standing there alone. She's been in this bit for at least a year now and she responds very well with it.
So, how do I get her to stop?
MDH took the pic for me while I was on her, reins in hand, so you could see the position of the bit "in use". This is the usual rein position for us when riding.