2-G HINGE MOTION Direction Control (2-D) means Clubface alignment control. The Clubface can make three motions through Impact - Hood, Close and Lay-back. "Hooding the Clubface", normally, can only reduce the Clubface Angle so only the Putter can actually be Hooded to any advantage (2-B), (2-C-4). Of the two remaining, we can use one or the other or both. That is - "Closing" without "Lay-back" (10-10-D). "Lay-back" without "Closing" (10-10-E) and simultaneouus "Closing" and "Lay-back" (10-10-C).
Doesn't tell me what Lay-back IS. I don't know what "hood " means either (I thought it meant 'closing'). The only other motions I can think of is (1)none and (2)opening.
The only other mention of Lay-back is in..
11-10 HINGE ACTIONS
Des. Term Description
A Horizontal Only Single Hinge - Closing Clubface - No lay-back
B Vertical Only Single Hinge - Clubface lay-back - No closing
C Angled Single Hinge - Simultaneous closing and lay-back
D Dual Horizontal Dual Hinges - Closing Clubface - No lay-back
E Dual Vertical Dual Hinges - Clubface lay-back - No closing