Sean, actually "skin effect" works the opposite way from what you think, if I'm reading your post correctly (and I may not be). That is, at higher and higher frequencies, a solid core wire of a certain gauge will transmit current (i.e., electrons) worse than a bunch of paralleled smaller wires that make up the same gauge. This is because skin effect causes the electrons to travel on or near the surface only, and stranded wire has much more surface area than solid wire of the same net gauge. Again, this really doesn't come into play until WAY above the audio range, at which point all kinds of things are different and solid-core wire has other benefits as well. That said, I'm a big fan of solid-core wire for audio use as well. The problem is that gauge is one of the most critical properties determining wire performance and "sound", and 10 gauge solid core wire is stiff as hell. Thus the preference for stranded conductors or solid-wire Litz windings in most people's setups.