Noone knows exactly what those .mov files are encoded with. The header hints at Cinepak, but the compression artifacts look entirely different than both Conepak and Truemotion. It looks very similar to MPEG-like codecs, with ringing artifacts and "smooth" macroblocks during heavy motion.
I am pretty sure about reading somewhere about a Saturn game that used a software MPEG decoder, and also supported the VCD card. That way you got to see the same FMV files even without the VCD card, but at a lower framerate or something like that. The audio wasn't MPEG, it was ADX.
Maybe that's what GameArts used?
(BTW, the rason the Grandia videos look oddly pixelated is because GA had the stupid idea of running them in high resolution mode, and scaling them up, in a pathetic attempt to make it look sharper - so it got scaling artifacts, due to the non-uniform scaling, and shimmering).
