Hopping back and forth between the different incarnations of Star Trek, when watching Enterprise I noticed in the episode in the first season when they meet up with the Vulcan group that tries to find balance between emotion and logic, when one of them shows T'Pol the mind meld, he calls it a lost technique or something that hadn't been practiced in years. Considering this incarnation of Star Trek a prequel to the others, how then did the knowledge get passed on later where someone like Spock would have picked it up and learned how to use it when the Vulcans seeking balance weren't well looked upon?