The forearms should be inline with the puttershaft. It is the same thing as going to impact fix with the right forearm in plane with the shaft (12-3-0) Section 2 Number 6. With putting the shaft will have better support with the putter and rear forearm in plane with the putter.
The reason for the left forearm in plane is a matter of sameness and a matter of alignment. With the left and right forearm in plane (in line) the shoulders will have a better chance of agreement with 10-9 "combinations of impact and address positions for the hands and the body (in relation to the plane line)." While it is a variation to use 10-9-D for putting it is advisable to have a body which is parallel to plane line.
From there you may have a long putter (35 inches or more for traditional putter styles) which will have the elbows bent or a shorter putter with the arms extended. Both should have the eyes over the line of the putt.
Hybrid Mode
