I'm a HDV newbie and I'm trying to get my brain wrapped around some of the finer points.

Take JVC's 6 frame GOP: Does the encoder simply take 6 I-frames and compress them into IBBPBB and then move on to the next 6 frames and do the same? Or is the process more complicated than that?

It works the same as any mpeg2 compression does, just like a standard 15GOP DVD. One I frame for how ever long the GOP is. In this case it would be 6. So in the JVC's case it would repeat that GOP structure 5 times a second.

Excellent thanks.