I would say 90% of the time it's a waste of time.
I dunno man, maybe
@Chi Town is right - throw a simple one and see what bites
I wouldn't explain the situation to her because if you message a woman saying "Hey I added you by accident" she will think you're being indirect and perhaps even insincere. It's like your hoping that SHE will take the initiative instead of YOU (the man)
Chi Town is right......and I have gotten far more lays through FB than all the dating apps combined (havent been on OLD in forever).
-There are already common friends
-You can scan through her pics and have common interests for conversation
-You are not some weirdo living in his mom's basement as she will see on FB
The key to FB is to show good pics and status. You can show status on FB where you cant on OLD.
I keep it simple. If an attractive chick adds me on fb, I always see if she is single (either through her "about" section or through her pics- easy to tell if she is single or not). If so, and I dont see any glaring deal breakers in her pics (ex: smoking) I just send a quick message:
"Hey whats up? Do we know each other?"
If I added her, I will simply say "You look familiar. Have we met?"
My next response is based on her response to that.
If she says "Hey there. No I do not think we have met" I will just come back with "Well thats unfortunate on both sides. We should make that happen".
Dont be thirsty, be chill and take a swing. Sometimes it works out, sometimes it doesnt. Nobody bats 1000%, but .400 is pretty damn good and will keep you in the league!