I think the flaw in the "new system" isn't what Mero said, but what you, yourself, said,
It shouldn't work like this. As I stated earlier, I don't have to shove pipes all over my house to tell it to turn off my stove when it's not in use. It has a handy little switch on it for me to turn it off at will. Obviously, having every mod auther who uses MJ power implement a built-in power-switch is unfeasible and won't happen. But with the way MJ is currently being restructured, (and if I understood what KL posted) this would have to happen in order for any machine/mod using MJ not to drain while not in use, or every one would have to accept a redstone-signal-on/off switch (in essence requiring everyone to hang a million pipes/gates everywhere for a truly automated and efficient system) Again, from what I understood, BC is basically setting up how they feel their power should be used/distributed with no room for another mod's input. (In their new system, you have no power-loss over distance, you can't add a % to powerloss if you wanted to, and machines would slowly lose their "charge" over time, so if the machine is actively connected to the power grid, it will constantly use/lose/drain power.)