When you are in the tunnel leading to Magus (after you've beaten Ozzie), you'll notice 6 bats coming after you. Yes, you can fight them, and yes, it's worth it. Wait till they are all in one massive group, then use Crono's Cyclone or Slash (Cyclone much more often, but Slash helps to keep it from monotony) on them. You'll get 12 Tech Points. Walk into Magus' area and leave, then repeat the process at the top of the stairs. I almost had Confuse before I fought Magus thanks to this trick (and boy, was fighting him easy).