how do you spot an asshole? I don't know any hard and fast rules, but when did Dom become a title and not a predisposition? just because someone gets off on turnig somebody on, dosen't mean they can do that from the first conversation. that in itself is an example of assholery to me.
You just don't start off a conversation that way. and i think that any decent human being knows it. if you are interested in developing a relationship with someone, well, you might want to know what they look like- the online thing is a bit weird to me- but if someone isn't polite, involving you in a real conversation, trying to see if they have a connection with you- then they are most definitly an asshole, and not worth your time.
I think that a D/s relationship needs so deep a level of trust that you have to have that first.