Well there's just too much stiffness involved in formally asking someone out. I think that's why it so rarely works. It just doesn't feel natural to either party - for the person asking it's a great source of anxiety (whether they have SP or not) and for the person being asked it's a tense moment whereby they're put on the spot. Every time I've hooked up it's been through a natural situation where things just sort of came together. There was never any official asking-out on my part, it just kind of happened. However, since I'm deathly afraid of heights I'd still go with asking someone out, even though that's just not the way I do things.