Heat exposure is very effective, but without permanent adaption of relative humidity during the heating process the wood dries out. In consequence it shrinks and cracks.Brad wrote: I would believe that a few days in an oven at around 150 degrees would be effective.
Having said that, I don't know if such an exposure would have a negative effect on the finish. I wouldn't believe it would, but I don't know for sure. Perhaps others can weigh in.
Better leave this to firms specializing in this area.