How well would it work to have the following setup with the obvious desired effects.

I want to take an electric guitar (les paul to be exact), and run it through an A/B switch, leaving the switch on to activate both amps on at the same time. from the A/B switch, the signal will be split between a bass amp and a guitar amp. If i turned all the lows up on the bass amp and maybe had an octave pedal on the bass amp side, would that make the guitar emit enough low tones that the bass amp would broadcast it like how I'm wanting it to?

btw, through the guitar amp it'd sound like a regular distorted guitar
You can do whatever you want! But a Cheap 'Y" cable will give you the same configuration and wiring for less money. Be aware that you are putting two loads on your guitar output signal level so each amp will recieve 3dB less power or 6 dB less voltage (double termination) so you'll need to crank the inputs on each amp accordingly. SRV used several different combo amps to balance his sound and who's to say that if you did this and played with the tone controls you won't get something you like out of it?
BTW Octave pedals create a signal above your instruments not below so it wouldn't do anything for making your guitar sound like bass if that's what you're after! There are efects that do perform this function.
Moving on.....
^Digitech Whammy has the option to go low an octave, which is what Jack White uses in 'Seven Nation Army'.
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I believe the boss Super Octave has the option of 1 or 2 octaves down, and 1 octave up. Unless I'm looking in the wrong spot, I found it easier to find octave down pedals than octave up.
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