That'll work reasonably well for a low-Z active input. Unfortunately, I don't think it will make your hi-Z passive pickups very happy. If this is going to be first pedal in the chain (usually the best place for a compressor) it probably won't produce acceptable results.
You could put a buffer in front, and probably get it to work. The easy way to accomplish this would be to use about any big name pedal (non-true-bypass, buffered like Boss or something) in bypass mode before the split. You could also google something like "effect loop pedal schematic" to find a DIY solution.
Doesn't matter what the pedal is, really. You're almost assured to need something acting as a buffer at some point before the split. It's not going to hurt anything if you want to try without, though.
I have some concerns re: the mixability of the signals as well. As is, all you'll have to adjust the balance between the effected and dry sounds will be whatever output level control is on the pedal. This could work fine, but things like overdrives and compressors generally have the capacity for a lot of gain.
ChrisK, good point - I forgot all about that - the phase reversal combined with the dry signal will cause cancellations. End of experiment. That's why the Barber mentions the "parallel compression" thing.
But I'm still interested in doing this with an OD though. Do OD's have phase reversal? Years ago I sorta tried it with a Scholtz Rockman, but without the resistors. It sorta worked.
Are 10k about the right value for the resistors for this with an OD?