About primal tempering: It's a simple process; you just bathe the victim in the primal's aether. You don't need the primal itself to be there. What the beast tribes do, is save samples of their primal's aether, so they can still temper people without a full-blown summoning. This has also been seen with the Sahagins (a beast tribe daily quest involves rescuing some prisoners who were being dunked in Leviathan's aether) and the Sylphs (those things emitting gas in the Sylphlands, on the world map, are actually pumping Ramuh's aether into the air. Anyone without the Echo cannot stay for too long around those spots.).

Xelphatol also showed that it's possible for a primal to be summoned only momentarily, so that's how the beast tribes get their primal aether: summon while we're not looking, with only a small supply of crystals.