Yes and no. I will agree with you in regards to true gems are never shared. As for the numerous sessions to open them up, it is not always the case. There are usually two critical factors, at least for me. One, they are horny. Two, they find you attractive. Here in Toronto I have yet to find that one semi legit gem that I have been able to get from HJ all the way to FS. DATY is the most I've ever managed to squeeze out of a chick.
These days I stick with the places that provide insurance receipts. One, I save a ton of money on door fees. Two, I know the chicks there are usually on the restrictive side and I actually get a sense of achievement when I get anything extra.
Most of the money I save goes to my Asia adventures. And even there, I don't seek out the FS girls. I purposely look for the girls that list themselves on the major websites, while also advertising that they are a NO for FS. That's when I go on the hunt. And usually I look for a few things. One, they don't have that pink fluorescent lighting. Two, they don't carry condoms around. Three, they never mention extra tips for extra service. Four, they get wet as fuck. That's when I know I got a shot.
I know I've made a post before about this, but you gentlemen ought to just save up money and buy yourself a round trip ticket to Asia. Hong Kong/Shenzhen and Macau/Zhuhai are my two go to cities. If you dudes are even half decent, you will always have a fighting chance even with the civilian girls.
A lot of you are spending upwards of $200 (door fee + tip) just to fuck a chick for an hour. Five times, and that's $1k and that's enough for the plane ticket.