I am not sure I understand this correctly. Are you talking about playing back videos from the VIRB directly without importing into VIRB Edit?
If you use VIRB Edit to import, the videos will be copied to your hard-drive and it shouldn't matter if you use the card directly, or the VIRB.
I also have this jerky problem, however my computer is up to requirements and the video is fine if I watch it in media player, however that means I can't have all the overlays which was the point in buying the product!