You can't think of 'lectricity in that way. It travels the path of least resistance. The amount of power lost by the rear speakers is proportional to the input impedance of the power amp. If it's designed properly, it should have a very high impedance which will minimize the amount of loss to the rear speakers.
I'll refer back to my last comment in post #35 now & shut up.
BTW Eric - just rattlin yer cage Dude. Since yer so young, I didn't expect you to remember the old days when RCA connectors came on nuthin but twin conductor. Nowadays you can even drive video through "good" RCA cables.