Right Knee

[DDL]

With the exception of standard knee action where the right knee straightens on the backswing, there isn't any specific mention of the right knee on the downswing. THe left knee can either straighten or maintain its flex. I can only assume the right knee maintains its flex. Based a lot on Hebron's book, where he advises the right knee doesn't move until the hands pass the right knee. What is the TGM way? I am surmising that striaghtening the right knee too soon, or at all would disrupt swing radius, and the pivot in general.