Specialization has advantages. It is obvious that piano movers need skills and experience distinct from refinishers and that bellymen, key coverers, and action workers need skills and experience almost entirely different from the first two. You would not expect a mover to be expert at stain matching or a refinisher to have the muscle or know-how to get a heavy piano up a stairwell.
The differences between what it takes to be belly, key, and action people is less clear, and in our industry, often all hats are worn by one person. But you can't expect to be as knowledgeable and expert at three (or five) things as you would be at one of them if you specialize. We feel that separating these functions benefits the job and the customer.
Take Mike Morvan's key work. Mike has three Bridgeports set up with custom designed tooling, a 6X10 CNC machine that cuts in three dimensions, and traditional factory ivory working machinery and clamps simply not available to the rest of us. The volume of work and meeting the expectations of the broad range of his customers compound the progress in tooling, procedures, and quality his shop can make.
Meanwhile, Mike has an ongoing feedback loop through Chris's installations. Mike has the specialty shop under his independent and focused management, but with the benefits of immediate "in-house" critique from the action shop.
A good factory divides up the spaces and personnel pragmatically to maximize function and efficiency. Ours is a variation of this model applied to piano rebuilding.