Well, most everything you do in premiere require re-rendering, like transitions, titles, and clip movement, etc. If you're just appending different videos together, all with the same resolution and vbr-capapble codec, then look into VitualDub. Premiere's too fancy for such a simplistic task, it'll assume it has to change something...I think. ----------------------------------------------------------------------------------
...but I'm just a C man trying to see the light