I would think that that would work yes, but for hum cancellation reasons, I always thought it better to run just the battery in the guitar. Batteries are technically better for all the pedals too but I got sick of dealing with that many years ago. Using a battery for the guitar is just one less ground loop to worry about IMO. But yea, that should work just fine running power to your guitar's buffer. What I really wish I could find is a wireless onboard guitar FX loop. Going wireless is the ultimate in hum cancellation but unless the obel is too,..
When the secrets all are told,
And the petals all unfold.