"You don't believe that a sufficiently intelligent computer system can coordinate to reduce overuse of lines? I.e., deliver line X to 10,000 geographically separated people?"
Pickup tricks are like financial arbitrage. Once enough people learn about what works and do it, it stops working.
I'm not saying that this idea won't make money (like I said, Mystery seems to have done well for himself selling advice), I'm saying it likely won't accomplish its stated goal of getting you laid more often by giving you the "winning" pick-up lines. Any effect is more likely than not going to come through playing the numbers game.
"As for dating/pickup, I don't believe it's zero sum. It's not a competition for a fixed set of prizes, i.e. 5 girls at the bar, all of whom will go home with someone."
It is in that no one wants to make a bad choice. People (at least girls) would rather not sleep with anyone than sleep with someone who is relatively less attractive than the possible alternatives. It's the paradox of choice.
"I have it on good authority (read: "spreadsheet pickup guy", who's name I'm hiding for obvious reasons) that this is false, and conversion rates can vary 20-30% (sometimes more) based on approach and profile."
Obviously there are some things you can do that will turn a girl off less than others. But how does that negate my point? Girls will sleep with guys they think are hot even if they don't think those guys are particularly intelligent or humorous.