My solution uses rackmount gear.
[color=#0000ff][b]Bass --> DI box --> XLR balanced signal --> Bass pre-amp --> Power amp channel #1 --> Bass cab #1[/b][/color]
[color=#0000ff][b]AND[/b][/color]
[color=#0000ff][b]Bass --> DI box --> 1/4" unbalanced signal --> Pedal board --> Power amp channel #2 --> Bass cab #2[/b][/color]
For the avoidance of doubt, that's only ONE bass and ONE DI box, using that DI box as my signal splitter. Obviously the DI box can be on the pedal board without actually being part of that signal chain.
Note that the bass pre-amp does not have to be a rackmounted Demeter or Avalon unit ... it could just as easily be a Sansamp or a Dave Hall pedal.
I'm lucky enough to have some very good quality kit, so the only really weak parts of the entire chain are the cables, especially the patches.
Having said which, I'm not exactly recording [i]Dark Side Of The Moon[/i] so I doubt anyone (including me) would ever notice.