I would kill for a standard middle seat compared to the middle seat I get stuck in sometimes on my hour long commuter train.

It's a three seater that comfortably fits two. Not only is it a tight for for three, but there are no arm rests, meaning you are squeezed shoulder-to-shoulder the whole time.

I've taken other trains (notably NYC) that don't seem to have this. Only the MBTA seems cursed with this layout. Wouldn't be a huge problem if the train wasn't standing room only (for at least a half hour) meaning people are squeezed as-is.