Too big is something not often talked about, but I'm sure it happens all the time. I'm larger than average, but by no means huge, and being too big has been a frequent problem my whole life. I'd guess 2/3 of the women I've been with, I've had to be careful and/or not been able to penetrate fully. It kinda sucks, frankly. Having said all this, I'm only 7.5", which is a bit above average maybe, but you poor buggers with 9"+, I don't care what anyone says, I KNOW that your sex life must be frustrating.
As for protocol, I don't feel like I personally need to do anything, but for someone in the position of the OP, I think you're doing everything you can do, so probably you're fine,yeah? Unless you're losing $ regularly due to providers canceling on site/sight; is that the case?