Can't help but feel sorry for binocular dude. He must've been hella annoyed. At least Tidus put his binoculars to good use.

On a more technical note, if you want to make Kimahri useful, teach him Steal and Use ASAP. I've also heard of people just saving his Sphere Levels until Spherimorph and then actually teaching him Holy right then. And I have to point out that you wasted 1000 Gil on O'Aka. 1001 Gil is the sweet spot, though 10001 is the best you can get (not worth it though).