The experience I'm relating to you just happened a few days ago. I have heard about this kind of thing happening but I never imagined I would have any experience with it.
My wife and I were in Boston just the other day. It was during the week smack dab in the middle of a work day between 11 am and noon. We were having a nice leisurely day starting out late to go see a few sites in this very historical city. We had made our way to the "T" heading for State Street. It was very crowded on the line that day. Our timing wasn't to bad as we were able to enter the train. Of course everyone on the train is squished body to body.
My wife and I were chest to chest in the car. It was kind of quaint as we were feeling quite alone crammed in with hundreds of others. That particular car was very loud, I didn't know if it was because of all the people or if it was overdue for maintenance. Anyway I couldn't tell if people were talking or not. My wife and I didn't say anything just cause of the noise level.
At the next stop it didn't seem like anyone got off but more people pushed on. As the crush tightened I had to step to the side to make room. This pushed me away from my wife who wasn't able to move from her spot. Now there were two of three people between myself and my wife. I had to look around the guy in front of me to see her and we give each other a smile.
We road along like that for only a short period when there was a shift in the crowd that wasn't related to the movement of the train. I looked around the guy in front of me, whom had his back to me, to see my wife but her head was down and she was mostly hidden by the guy closest to her. His back was facing me and he was a fairly large guy. The car shifted and I move just enough to the side to get a better view of my wife. I could mostly see her from the shoulders up but I could catch a glimpse of her waist now and then. At this point we were at another stop and this time I don't know if anyone got off or on. I really couldn't see how anyone would be able to enter with this many people crammed in.