My gay-dar is so off

One lesbian cousin, one gay uncle, a dozen gay and lesbian friends over the years, plus having dated more bi-sexual men then I want to admit to...you would think I'd be able to spot a gay man five miles away.

But no. Sadly, I still have no solid clue half the time, unless the guy is so over the top flamboyant.  I could chalk it up to the fact half the men I've slept with have been bi-sexual, or I could put it down to evolution. Sex and the City (season 2 episode 23 {of the series. #11 for the season} 'Evolution') dealt with the confusing phenomenon with the gay-straight-man-straight-gay-man storyline.  The gay-straight man is a straight man who has been overexposed to musicals, furniture, and fashion while the straight-gay man is a gay man who plays sports and won't f*** you.  (that's a quote from the episode) 

Then there are the gay men who flirt with you...which is another issue for another time.

Anyways, I met one of my neighbours earlier when I took the trash out.  I was slugging towards the garbage shed, when I saw this really good looking guy come out of the back of the building also carrying his trash. The guy spotted me, and kept looking at me. We got there at the same moment, and instead of rushing in and slamming the door in my face like some of the others in the building have done, he nodded, said hi, opened the door took my trash from me, tossed it in then carried his own in. The whole time he had this look on his face that can only be classed as a sheepish grin.

Now, when I first spotted him come out of the building and around the parking lot, something in his movements screamed in my mind that he was gay. But the closer I got to him, the less that seemed the case. His body language changed, and the way he looked at me was the same way this one ex-boyfriend used to.  There he was, smirking at me with a seductive look in his eyes, standing so close to me that I could feel his nervousness as he asked me if I had just moved in, while he fumbled with his keys for the garbage shed. And then this car pulled up and he says "there's my guy." and got into the car.

What the hell?  What happened here? Was I right with my first thought that this very good looking man is gay and therefore unavailable? Cause there was an attraction happening. Or, and I dread to think it, have I stumbled once again on another bi-guy?

I can't tell anymore. I'm just going to start assuming that every man left on the planet is bi. That way I never have to try to figure the score.