google"drop crotch pruning". Al

The way I see it is you cut the branch to a lateral growing in the direction you want the canopy to go. Usually this is an outward growing lateral. Sometimes I do a heading cut, like if there is no lateral. But usually if there is a strong upright shoot with no laterals, I cut out the whole thing.

One source said that you should never attempt to control the height of a fruit tree using a heading cut"
Never say never. It is perfectly legitimate to head a CL in the dormant, but better in the summer. In French Axe it is better to bend it over or to head the CL to a side growing branch that is vertically oriented and it will then become a weaker growing CL.
I can think of two Golden Delicious orchards near me:
A) very beautiful trees CL that are absolutely identical to each other. Planted close and not too tall. A "model orchard" that is exhibited to growers from other countries.
B) big old trees in the "old" open vase style. Only 108 trees per acre.
B outproduces A by 25%. It is far more profitable, but you probably wouldn't start an orchard like this today as time is money and it is slow to come into production. But A took a lot of money to get those trees to look uniform. Lots of training and cutting and that delayed production. More expense for posts and wire. We need to remember that we want fruit and not wood. There is a "happy medium" and it depends on where you are, what you want, what you are growing, etc.
I would dismiss hard and fast rules.

Al, FruitNut, Geraldo_Linux
Thanks for all the information!
It sounds like I didn't do too bad of a thing. I did do a summer-prune heading cut, but really, there were no laterals in that area of the central leader that I could cut back to. At the time that central leader was about as big in diameter as my index finger, and the cut was made about 8 feet high about as high as I can reach. Without that cut, the tree was probably approaching 11 feet high (3 feet of long straight central leader prune) Now that I've made the cut, just below it I see that two new branches about 5 inches long have come out just below it, as one might expect. I'll probably train those to do something productive. Thanks again,
-Glenn

Of course you control height of all fruit trees with heading cuts to a side branch located at the desired height. Someone must have been confused with the Shigo mantra of "no topping of trees", which is about forest trees and is even simplistic in that context.

Central leader trees are maintained by heading cuts every season and with the removal of entire branches on the top half of the tree once they become too large diametered and too difficult to keep from shading lower branches. Properly positioned smaller replacement branches should already be growing to take the place of such branches when they are removed. You plan at least a year ahead.

Regarding Orchards "A" and "B"

I have next to no experience with apples but I like reading old horticultural and agricultural literature and see a fair amount about them. In reading material on apple tree pruning from the 1930s and 40s I will see it mentioned how the US and Canada went through the central leader to open "vase" transition in practices en masse at least once before. It was said then (no later than 1940s) that old orchards (planted 1870s) that were CL style were commonly found still doing fine, while orchards of the open style many decades younger commonly were deteriorated by breakage at the crotches between main trunks or main scaffold branches. How do these observations hold up today, with perhaps using better tactics it training the open style?

I tend to think that properly open center trained trees can work well if you create scaffolds with strong unions. This can best be done by starting off with with a central leader shape and selecting moderately vigorous branches as your permanent scaffolds. Moderately vigorous means less than 1/2 the diameter of the trunk at the branches point of attachment to the trunk. The scaffold branches should be growing at about a 65 degree angle (upward) from the trunk (spreaders may be helpful).

After a couple of years you cut off the tree at the point of the highest scaffold and eliminate all but 3 or possibly 4 permanent scaffold branches(depending on the trees willingness to send out vigorous secondary branching, twiggy trees needing only 3). Branches should be envenly spaced around the circumfrance of the trunk.

I manage plenty of 100 year plus old apples trained to open center that do fine. That being said, I train most trees I manage, even stone fruit, to a modified central leader these days. Once you know how to do it such trees are easier to manage and take less space in ratio to productivity.