I'm involved with the rebuild of a fabric biplane currently. To cut costs the owner has decided to have the top wing rubbed down and repainted rather than remove the fabric, inspect the wing, recover and repaint.
I'm having nothing to do with the top wing as I know that the previous paint scheme will show through as outlined above by HP. I think that as the fuse, lower wings and empennage have all been beautifully recovered (Stik takes a bow!) that he is short changing himself and not doing the rebuild full justice.
Yes it can be done - but I wouldn't do it. No problem with touching up fabric that has suffered damage but a repaint is NOT a good idea - after all you end up just adding weight to the airframe.
You could also try Rob at aerographic.com, his work is exemplary, as I'm sure HairyP will testify to.
Stik