IMO the ground wire should be as short as possible.
Hasn't caused a single problem yet. You also have to take into account with my install I had //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif no choice but to leave some slack or the install would have been that much harder to complete. If I only had a couple of amps I might have made a real short ground for them but when I have 5 amps running and they all need to find the common grounding point its not that easy.
On another note, what problems do you think would arise if "McGee" were to add a couple of feet of wire to each ground wire to reach an adequate grounding point.?? Personally, I don't think he would have any what so ever.
