Spock mind melds with McCoy and gives him his katra.
Spock repairs the ship and is fatally injured.
Spock tells Kirk “I am and always shall be, your friend.”
(Brings a tear to the eye, don’t it?)
Spock dies.
In TSFS, having had his katra reinserted, Spock repeats the words to Kirk; he spoke them after his katra was given to McCoy, how would he remember?
And if you can explain that, then explain this to me:
Sarek says, “I ask for fal-tor-pa… the refusion.”
Freaky Looking Vulcan Woman says, “What you ask for has not been done since ages past, and then only in legend.”
but Sarek also said earlier, “It is the Vulcan way when the body’s time is at an end.”
So… the Vulcans perpetuate a ritual where they store their consciousness in some unsuspecting rube’s prefrontal lobe even though nobody actually knows how to get the katra back out of said rube and back into some functional state?
Spock didn’t slump to the wall, catatonic, after giving McCoy the katra. In fact, he was functioning ‘normally’, walking, speaking, lifting the cap off the Wind Machine of Deadly Radiation, etc. No reason he shouldn’t remember what had happened after he had given to McCoy, that was stored in his memory, not his ‘spirit’.
I know, I know, but Sarek didn’t exactly go into detail about what a katra is: “his living spirit”. OK. Sir!
Think of the katra transfer less as a download and more of a pathway establishment. Spock opens a psychic connection with McCoy that allows his katra to transfer to the good doctor when Spock is through with it. After all, if he’d just dumped his soul into McCoy then, he’d have been a zombie for the rest of the movie, right?
On the other point, I agree with carnivorousplant.