I've been heading back my central leader, especially if I have a lot of growth - vertical growth, and not much for scaffold branching... I just started experimenting with notching or making a horizontal cut/slit above leader bud sites to try and encourage scaffolding also. My trees tend to have run away central leader growth and lack scaffold branching and heading seems to really help getting those side branches to take off.
Everybody out there seems to have a little twist on the art of pruning and Im finding that it is an art/science with a ton of differing opinions.
One thing I know is key is getting on existing limbs and training their crotch angles - Im always behind on this and the trees grow so fast that it always seems that I'm failing in getting out and making the time to do this and paying for it later. I have a bunch of older trees that have poor branch angles and are now breaking under fruit loads. Those older trees also have a lot of funky crossing branches and branches on the trunks that are now to close together. Learn to be mildly aggressive with your pruning.
So the last couple years I have cut back the central leader on my trees each year, and have been cutting back terminal growth on my scaffolds and being more aggressive with my overall pruning %. It may cost me some years worth of gain in overall height but, and I may be off the charts wrong - but I was told that it allows for a stronger core to the tree - stronger thicker central leader. Where I really fail is getting out there and getting spreaders or weights on the branches.