I never fully understood IC2's power system. I always understood it as Throughput and I/O. Throughput being the amount of energy a cable is capable of sending through, made easier by it being multiplicative. And I/O being what machines are capable of putting into the cable and taking out from it.
Batboxes can put in LV to any cable better than tin, but trying to put MV or better into a copper cable meant it couldn't handle the Throughput and thus melted. Thus Gold cable had 4x the capacity or 'pipes' of copper.
On the other hand, I remember trying to run a GT blast furnace and never quite being able to manage it consistently, until I hit on the idea of plugging power into an MFSU and then running that straight into an MV transformer. Previous attempts with an MFE failed rather depressingly. (And spectactularly at least once for some reason.)
You know I suggest Railcraft be thrown in, just because, but it does make moving IC2 power around more effective, unless you're powering your MFR stuff on RF. Nothing quite like seeing a pile of diamonds go sliding past on a steel box, full of expensive, difficult to produce power. Maybe some sort of barrel mod, since I'm still convinced it's the only bit of Factorization anyone ever used. That and the magic glass machine.