I did not really understand the mechanism until I rebuilt my stove. Once I saw it I thought it was pretty clever how they combined the cable with a looped lever and hinge to get the action and no sliding along the cable that could wear through.
I have noticed mine on occasion will hang up the very last little bit, if I pull the cable I can see and hear it pop full closed. But it is not much....
A couple years ago I thought maybe my bimetal was failed, I found the pocket clip from a mechanical pencil fits perfectly over the screw that clamps the cable. I attached it as a pointer so I could just ho much movement there was rom hot to cold. It is quite a bit, more than I expected, as you said.
Sticking wide open is not good..... never had that happen.