I don't think he is talking about true bi-wiring to separate connections on the speakers. I think he is just talking about doubling up the cabling vs. running a single cable.
In which case, I wouldn't think there would be any benefit to running 11g vs. 14/4 wiring and doubling it up. If the connection to the speaker is the same, then the result will be the same. In reality, if the run is within the distance in which 14g wiring is plenty, then doubling up or running a single 11g wire will show no advantage either way as there is no sonic advantage over a shorter distance with thicker wire under measured electrical results.
It is also absolutely insane to spend 10 bucks for 3 feet of cable. Get cheap, quality, copper speaker cable and be done with it.
100' of Monoprice 12/4 cable is 83 bucks. That's 83 cents a foot for quality cable and is likely overkill for most applications.