Well, I'm not one to brag but if you insist... I have a MSEE specializing in power electronics and motor drives. I've been working in the aerospace drives industry for 5 years. I'm not exactly a guru but I have worked with several.

That said... I have have nothing to add. LOL Well almost everything's been said but I'll try to clean it up.

1) Inductance from battery to ESC can destroy the ESC especially when you run the ESC at max rated cells (volts). 12 inches max is a good rule of thumb BUT reducing the loop area between the + and - wires is just as important. Twist or tie the wires (loosely) together.

2) Any length from ESC to motor in an RC plane will basically work BUT: [ul][*] you should still loosely twist/ tie the wires together to reduce radio interference. The three wires act like antennas and placing the three together helps to cancel the fields. Keep them away from antenas and servo wires. [*] you always lose efficiency from resistive (heating) losses in any wire - shorter is better. If you have to go longer, you should use thicker wire. (How big depends and too many things to make a general recommendation)[*] thick long wires are heavy!
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Jesse