Found it very interesting scot, thnx for the link

What I found most interesting is the technique he talks about for decandling black pine, by reducing needles all over the tree to equal the needles on the weakest branch and then to decandle all over the tree at the same time.

I believe he was talking about red pine when he said to leave some older needles, because red pines are not as vigorous as black pine

If you go to youtube, there are hours of video's of his demo's. You can probably write a pretty good book on the info you can pick up watching those vid's. The info he gives out is the cutting edge stuff of what he learned in college and what the latest techniques being done in japan where he studied.
 Many of the things he teaches is very different than what we have been taught to do. We only need to alter the timing to our climate. I have been told by Ryan that when you see the trees in Japan, what strikes you is how vibrant, alive and healthy they look. The Japanese have learned through trial and error what to do and we are lucky to get that info.
 I have mentioned the video's by Owen Reich and Bjorn also. If you have not seen those, you should! I'm too computer lame to be able to post a link to them, but perhaps Owen or someone else can. I know they have been posted on this board previously.

My understanding is that the new needles are your photosynthetic material and your old needles are your hormone producing material to help encourage back budding among other things.