In and out, no way, back and forth not likely either..Best answered by TKG, the extra wire is a redundant ground in case the other one fails..I wouldn't think .010 either would make a measureable difference, it wouldn't on my igniton...
I talked to Bobby Wilson at Cactus about the new 3W ignitions..They are designed to work with a NiMh battery and can be used without a regulator, up to a little over 8 volts..4.8 volts is too low and might cause the problems with firing at the wrong time...There are two small magnets in the hub, the red one is ignition and the green one is the other functions..They can work in line on the same hub without interference because the North pole triggers one sensor and the South pole triggers the other...