Just to confirm, re-breather is not required for Full Game, right? It's not a bug and it's part of the game since there is an achievement. Also, it doesn't save that much time, maybe 40-50 seconds to get it but collecting 8 health packs can take 3-4 seconds, each, and you may have to go to Medical twice because of that. (Or diving back-and-forth for air adds ~40 seconds.) I would say, everybody can choose how to do it.

Without a rebreather, many rooms need to be visited only once and you can avoid killing enemies there. You also do not need to visit the main section of the medical area twice. But then we will beat out the time of an hour in no skip run. As you wish.

Yeah, keep it easy to encourage more people to do a speedrun. Again, we can later add a 100% category where this is required.