[KTL]

The splines are not important. The pin that holds the fork into the release fork shaft is inserted into a hole in the fork that must align with a groove that goes all the way around the shaft. So that's why the splines don't matter. Any position of the shaft relative to the fork will work because the pin "doesn't care" at what position the shaft is at. The groove (instead of a keyway) lets the the pin go in at any shaft position, as long as the pin aligns with the groove in the shaft.