It seems to me that one could make some really high-quality bark chips and fibers by running something like a huge cheese grater lengthwise along logs before they were de-barked. Then there would be very little "powder" and lots of long, thick fibers or chips.
Or you could run logs into a veneer-cutting lath with the bark still on, and slice off a uniform-thickness sheet of bark that ought to crumble into really long fibers and no powder.
But the orchid and nursery industries seem to get along OK just paying for double-screened bark. I suppose the size of the market doesn't justify large investment or "bark research".
