Hinge the club at 45 degrees for a flat lead wrist
Porzak teaches the direction of the wrist hinge in the takeaway. He sets the hinge direction at 45 degrees, splitting the 90-degree angle in half, and shows that hinging too vertically (up in front of you) would 'cut' the lead wrist, while hinging directly behind you would 'bow' it. Hinging in that 45-degree direction instead helps flatten the lead wrist, with the trail hand on top.
Channel: PorzakGolf
Watch official source at 2:42Why this context matters
The 45-degree hinge line is marked on Porzak's alignment-rod station, so the cue is easier to see than to read.