I had no idea what this was. Third result pulls the main forum. lolBi-cut neck
The G&L Discussion Page - View topic - The G&L non-compression truss rod :
The Bi-Cut method involves cutting the neck blank in half longitudinally, making a route on the inside, inserting the truss rod then gluing the two halves together.
The new completed neck blank is then put in a Taylor press with approximately 350 pounds of pressure, assuring a nearly invisible truss rod installation.
The design goal that the Bi-Cut method achieves is exceptional resistance to warping and twisting, because the centrally located glue joint is actually stronger
than the wood on either side.
Cool!

