I tried out Kainz (the failed engineer; don't remember his localized name) for a while, and really didn't see the benefit in using him on the robots. The only thing I could really get to stick was Limit, and only some of the time. (I can already do that with Ann, using a weapon I don't even use, anyway.) Gaj/Gigaj and Ageia didn't really seem all that beneficial either, considering his fairly low supply of mp, and the fact that I now have Gizan casting items. I'm sure if I got him up to the level he learns Nasagaj, he'd be worth having around, but maybe later.
I got that no encounter trick working, also. Didn't realize I was supposed to use the examine button before. So I was walking around opening up the menu with C, closing it, walking a step, and so on. Was poking around on a Japanese walkthrough site, and saw another explanation of the trick; It does indeed work, I just didn't realize I needed to hammer the A button.
(I don't know if this is only in the mega drive version, but apparently you can make everything move in slow-mo by hitting the start button, then holding B. I thought that was kind of cool.)