Oh, IC. Well, he does not get along with Cat and Kryten. Which leads to the thought that it's a chance for him to get away from them. Lister he is fond of, yes, but not them... Many things tugging at him. It's a very complicated ep. It's worth a thread in itself.

If Captainly Rimmer shares traits with Rimmer, but is just the positive side of the traits (as I got the feeling from Hollister and Lister on the other side), he'd be very strict about rules and regulations, and impersonating the Captain would be a biggie.

I saw it as something like an inhabitant of Winter becoming pregnant when in kemmer - the pregnancy keeps them female when they would normally become neuter. The pregnancy ocurred in the parallel universe, after all, so it might carry its laws over until it is complete. To make a parallel - if Rimmer ejaculated with his massive cock in the mirror universe, then carried the spooge back over, I'm assuming the spooge would not decrease in volume on the normal side just because his cock is the normal size. Or if he had sex with Kochanski over there, I think she'd still be sore when they walked over. Effects persist.