FWIW, I've never noticed signs of interest from the opposite sex; it was only after the fact, when I talked about an odd occurrence, or someone acting unusually, that people told me that it was probably a sign of interest. I didn't start a relationship until I started making much more active moves; that took many years.
My point being, I don't think it's that unusual for many men to simply not notice these signs you find obvious. To this day I can't tell. I'd be having dinner at a restaurant with my parents and my father would tell me that the waitress was unsuccessfully trying to flirt with me!
(I mean this as no defense of Dave. My fault is never noticing and never acting when it's welcome; I have never acted without verbal or written invitation. It took my current partner sending me a text saying that she was worried I wasn't into her, before I knew I could move further.)
My point being, I don't think it's that unusual for many men to simply not notice these signs you find obvious. To this day I can't tell. I'd be having dinner at a restaurant with my parents and my father would tell me that the waitress was unsuccessfully trying to flirt with me!
(I mean this as no defense of Dave. My fault is never noticing and never acting when it's welcome; I have never acted without verbal or written invitation. It took my current partner sending me a text saying that she was worried I wasn't into her, before I knew I could move further.)