Very good article (maybe THE best article on the whole internets) on lat-pulldown technique: http://www.bodyrecomposition.com/training/lat-pulldown-technique.html Lots of pictures too, very helpful!
Another good article on lat Pulldowns. I liked it better than Lyle's. http://www.mikereinold.com/2010/09/lat-pulldown-how-to-maximize-latissimus.html
Both articles are great. "Pulling through the head" sounds at first painful in a humorous sort of way, but it makes sense. The lat pull down machine we have has two separate arms and handles so you don't have to worry about the bar hitting you in the head as you would with a traditional pull-down cable machine. During 5's, I am going to be adding sets of lat pull downs for "metabolic" work; still using chins as my primary lat exercise.
Today I tried the original Hammer Strength plate-loaded Pulldown machine. It allows you to do a wide grip pronated Pulldown "through the head" as the article above describes. It was by far the best exercise for latissimus dorsi activation I have done yet! Felt similar to pronated pull-ups. Here is a link to the machine: http://www.exrx.net/WeightExercises/LatissimusDorsi/LVPulldownH.html
