You can top it to any node you really want. From asking around the thread, I learned that you can really top it down to any node you want. The benefit of letting the plant grow out, 5-7 nodes, is that you can choose your strongest looking node, or most even nodes, if working with clones. Cut to the best node, transplant and bury the stem.
Even canopy is what you shoot for so you can get your lights as close as possible to get the most out of your light. Air flow is always important, For outdoor growers in the summer months in humid areas, and for people as myself who are in a small area, indoors, humidity can build up quite quick, like when the lights go out, so anything that helps air flow is a plus, I have soft ties on some of the main's on every plant, and they are anchored to the tomato cage. This will allow better light penetration and fight that humidity giving you better air flow. Just like nugbuckets did, I can move them around the cage, and tuck leaves my leaves, never take off the leaves, tuck. Even if you are not worried about height, getting a even canopy is the name of the game.
FJG