The thing is, as many people have pointed out in the past, BM is no longer principally a dating site, and with a membership consisting of only 25% female to 75% male it couldn't work as such. Its evolved more into a general social site and therefore the whole nod thing is totally confusing for most people, including yours truly.
And yes, the last person to Nod at me was, by the sound of it, a gay bloke living over 200 miles away, with no bike of his own, WTF ?!!?