Here's a picture of the great Henry Cotton showing the equally great Jimmy Bruen his idea of proper left hand action through the ball. "Who's Jimmy Bruen?" you may ask.
Jimmy Bruen may be the most naturally gifted golfer to ever come out of Ireland.
Before Trevino, and Couples and Jim Furyk the granddaddy of all loops belonged to Jimmy Bruen. The "Bruen Loop". A plus 1 handicap by age 15, at 16 Jimmy Bruen won the 1936 British Boys Championship with one of the most unique and powerful actions in the history of golf.
To get an idea of how unique and how extreme the Bruen Loop was check this position at the top. Taken from a great article about the Bruen Loop from TeeTime Ireland ( http://www.teetimeireland.com/teetimeireland/history.php?historyid=502 )
Jimmy Bruen Played on numerous Walker Cup teams and his mere presence on the 1938 team is said to have simultaineously inspired the GB&I boys and shook the Yanks up sufficiently to deliver a win for the UK team which would be the last until 1971.
Bruen was the last amateur to lead qualifying in the British Open and also won the 1946 British Amateur after a 5 year hiatus caused by WWII. It is almost certain that Bruen's trophy cabinet would have been crammed to overflowing were it not for the war.
In 1946 Bruen injured his left wrist lifting a heavy garden tile making necessary numerous surgeries on the damaged limb. He was never really the same and that is a shame.
Cotton is said to have worked with Bruen to develope a more conventional swing path and stated that Bruen was eqally impressive with a conventional swing path, but that the Bruen Loop delivered a power that even Cotton was hard pressed to explain. To quote the British I'm "gobsmacked" also.
Below is a beautiful and moving video of Jimmy Bruen. Behold The Bruen Loop!!