[Yoda]

Personally, I prefer the MacDonald Drills #8 and #9:

https://picasaweb.google.com/lynnbla...12149369669 0

These drills keep the upper arms close to the body while still encouraging a free Arm Swing. They can also be done while encouraging the upper arm structure of Extensor Action.

In my opinion, the 'under-arms towel drill' encourages incorrect, compressing (as opposed to stretching), upper arm pressures. In turn, this almost always produces a 'Body-controlled Hands' Stroke that:

(1) Inhibits the Arm Swing;

(2) Prevents a free 'overtaking' of the Body (by the Arms and Club) during Release; and

(3) Causes both the Hands and Club to be under plane in the Start Up, above Plane at the Top and through Impact, and again under Plane in the Follow-Through.