Honestly, I rarely "plan" to date anybody (in fact, the whole "dating" thing is new to me...in my life relationships usually just kind of happen organically). My mate and I are both of the same mindset, that when the universe decides to drop someone in our laps (collectively or separately) we'll go for it, and otherwise we generally aren't actively looking.

Which I know is no help. For me I think my best strategy has to make sure they meet my mate before anything happens - he's got a really good sense for people who might be a problem (I do the same for him), and I really trust his judgement (because I don't always have the best sensors on such things...and vice versa for him when he's interested in someone). They don't have to be in a *relationship* with him, but if they can't at least get along with him and be friendly, it's a fairly good sign there's not much of a future.