Smaller wires still provide benefit, just not as much benefit as larger, more current-capable wire. Like everything, just because someone on the internet got away with it, doesn't mean it's a good idea. Everybody's use is different - one person's version of "beating on it" may be another person's "takin' it easy".
So the effect of the caps is less because the wires cant flow the current given by the caps?
I'll go with 10 gauge, never hurts to have a bigger wire, it is just a bit harder to solder.