I know several P411 providers that will contact a few of the guys OKs as an added screening measure. I have no way of knowing who they'll reach out to. I also know several who save enough information for her to remember me by. That's specifically for reference purposes.
I'm not saying everyone should do that or has the means to do so, but that kind organization and TCB is something I appreciate.
P411 also has a place where you can keep notes or important reminders about a client. Its very helpful when giving a ref. I usually go to my notes on the client another provider is inquiring about and my notes often trigger my memory. Screening is what us ladies rely on so keeping notes or finding other ways to remember guys in order to be able to give a good reference is much appreciated by other providers.
P411 is a great site, but a lot of people are not on it. Since so many providers require references, it is an important topic.
Guys, your best bet is to make contacting your reference a part of scheduling your appointment. I personally do not ask for references, but I know girls that do and there are some problems. These issues only delay your appointment or even prevent it from happening. Noone wants that.