A little something McCoy said might shed a bit of light on this whole thing:
"They still go mad at this time. Perhaps it's the price they pay for having no emotions the rest of the time"
In ancient times, Vulcans probably didn't need
any pon farr to take a mate and go off to make little baby Vulcans. They just set their eyes on some pretty little pair of pointed ears and killed whoever stood in their way.
After the Surakian reformation, however, it was discovered that emotional repression only gets you so far. Sooner or later, something's gotta give, so the seven year cycle was begun, so that even the most repressed devotee of Kohlinar would have to go get busy or risk insanity as the emotional pressures reached critical mass. Or maybe those monks are all eunuchs, in which case Spock got out just in the nick of time.