"Training young trees using weights or bracing sticks to create 90 degree angles is ideal. I use concrete weights that were created using Dixie cups for molds and old house electrical wiring. The wire works well so you can wrap it around a branch that needs training and then easily undo it and use it else where. I have different sized weights (different sized Dixie cup molds). Bracing sticks I do not use but, years ago farmers did. They consist of 1x1" wood 4 to 8" long with double sided nails at both ends that can be placed in a branch crotch to spread the crotch.
Hang the weights on branch that you want to bring down to create the 90. When you first hang the weight make sure to check on the branch / tree the next day, you may need to move the weight back towards the trunk as the branch may be hanging to low. Another benefit of training apple trees is that the trees will bear fruit earlier (at a younger age). It tricks the tree into thinking it is older than it is. Tree limbs naturally bend down or become more horizontal as they grow in length & diameter (becoming heavier)"
With that sort of an answer from an experienced arborist, I feel much more comfortable about the idea of training a tree. I am of the opinion that pruning is still a mandatory exercise, as training a tree to grow at 90 degree angles does not wholly prevent inward facing or misbehaving shoots. It does seem however, that through training, a grower can reclaim what would have been pruned stock and in so doing, make for a healthier tree that bears fruit earlier.
Nate, well done, and carry on kind sir.