How can one generally determine whether a person is fulfilling his whitelisting function or not?
Read:
Now the tricky part: apart from including your Bitcointalk username, you'll need to convince me you deserve it. I know this sucks, and I hate jumping through hoops too. But it's the best I can do to help new Bitcointalk users without giving spammers a free pass.
If there are no statistics on rejected users?
If I'd provide those statistics, you'd say you can't verify them. I can give you an estimate: I must have rejected about 1000 requests. About 20% of them didn't even send me their username.
Consider this the last time I'm feeding this troll.