That is exactly what i did (ran both wires the same wall).
I can not see the wires at all, but I was somewhat fortunate in that the previous tennant of my home (yes I am renting) had lifted up the carpet before and made it easy to pull the carpet back.
The down side is that the carpet tacks strip has lost some of its "bite" from previous people constantly lifting and putting back down the edge of the carpet....
If you do this I would reccomend testing to see how easy the carpet comes up and goes back down in an inconspicuous spot... and the key would be to lift it back, put it back down, and never touch it again. If you keep lifting and replacing the carpet it may eventually weaken the 'bond' between the tack strip and the carpet.
