Thanks. Interestingly this is not a recent thing. I worked on the restoration of 17th century manor house near me and a part of the work involved repairing the numerous dormer windows. The posts all needed replacing and so we kept the carved lintels. The tenons were 3cm wide and 3cm from the external (reference) face which meant that the faces were aligned. While I'm not certain that the dormers were original, they were certainly centuries old.

I've subsequently used the same technique when building a frame which was to be glazed directly as this kept the glazed surface planar.