Well it's "technically" survivable, but for me the funniest line in the whole Apollo program has to be Dave Scott's.
You see, they had some trouble separating the LM from the CSM on Apollo 15 so Al (CMP) went down into the tunnel to check if the umbilical cord was plugged in.
At 100:21 Dave Scott radios from the LM to Al: "Hey, Al, I sure hope the Extend/Release switch was Off when you went in there". Meaning that if the probe switch wasn't Off and he would reconnect the umbilical, the probe would imediately extend and separate the two vehicles. Only with the CM's docking hatch opened and All inside the tunnel the CM would decompress ..maybe even flushing Al outside. I think they were all suited up, but even so, having a floating CMP in lunar orbit was probably a mission breaker for them.
I still chuckle every time I hear that line.