If one looks up the word, ‘cool’ in the dictionary there will be a photograph of Alan Shepherd, to whit:
During his entire, sub-orbital flight his heartbeat never rose above 80 beats-per-minute. All other astronauts were in the 150 - 160 beats-per-minute range or higher, including Neil Armstrong. He repeated that same ‘cool’ for his subsequent flight.
Of course, he was a Navy pilot. :’)
During Apollo 14 they were having a problem getting hard dock, and after they finally got it, NASA told them to undock and try it again, because they wanted to make sure both the hardware and the software (IOW, the crew) were in proper working order, the concern being, docking after the LM returned from the lunar surface.
Shepard didn’t want to it, said if need be he’d suit up and hard dock the damned things by hand. NASA didn’t go for it.