I rarely drop my stirrups on purpose, but I have lost them and not bothered at trying to get my feet back in.
I regularly dropped them when I was working with Dude because he was a rearer and I knew he had the potential to go over if I didn't catch it beforehand, which happened sometimes. I don't think of my stirrups as anything other than an asset to me hauling my ass up on a horse or using them to bring myself centred after leaning halfway off my horse to grab something. I don't need them to stay on, but like mls said-it's much easier to control a misbehaving horse without stirrups in the way of where I want my feet to be.
I've never intentionally dropped my stirrups on Lucky, Fancy, or Poco like I did Dude though. If he acted up and got really light on his forehand I'd drop them and continue what I was doing, just because of the fact that my feet DID get stuck in those stirrups because they weren't wide enough for my boots/feet. I now have stirrups I can slip into and out of easily, so I don't make it a point to try and take them out, because 19 times out of 20 they will fall out on their own if I go flying. Because with the wide ropers or oversized stirrups come off as soon as I bring my heels up, but the barrel stirrups would constantly get stuck, even if I barely had my toe in them.
So..moral of my babble, if the stirrups are a bit too small, I'll ditch them, if not, on they stay unless they accidently fall from my foot. :p Though, the oversized ones constantly got in my way when I dropped or lost them, so I tried to keep them on as long as possible while working out the kinks. If they don't get in your way though, I don't see an issue dropping them, personally. Because I can now do just about anything I would in a saddle bareback (for what I generally do around the barn whilst training, barring shows), I don't have an issue staying on if I drop or lose my stirrups. Posted via Mobile Device