I find different varieties respond differently to topping. Some will grow laterally from only the topmost node(s) while others will tend to bush out from a greater number of nodes. The ones that grow from only the topmost node will typically need to be topped early and more than once to create an early "bushy" shape and will also tend toward longer internodal spaces making height control more challenging. Most varieties seem to arrive at a bushy shape eventually, especially when grown outside, but many will reach something nearer full height before they develop significant bushiness. I'm of the opinion most will also produce at or near their optimum pod-weight potential without topping. I'd definitely read studies on the effects of topping on fruit production - heck, I followed NECM's thread all season - but I suspect there are so many variables among plant variety, growing environment, and timing of topping(s) that it would take extensive research to account for them.
Generally, I top only indoor plants. I do it when I'm trying to keep more of the plant foliage in the more effective lighting zone of artificial lighting or to prevent the plant from getting too tall for my lighting setup. Outside, I'm not concerned with topping, but with removing the lower leaves and/or branches to "lift" the plant and avoid splash-up of water/fungus/bacteria, improve air circulation, and keep pods up off the ground - the "little trees" idea.
The varieties that tend to grow tall early without much lateral branching (even after topping) I tend to top the earliest, although generally I would favor topping early vs. later in almost any situation, especially if rapid pod production were a primary consideration. When you have to top multiple times, fruit pod production is likely to be deferred longer, though peppers ultimately seem to have an internal clock and will simply start producing at some point.
I have a few cardenasii plants inside right now and I top them quickly and repeatedly, because they want to grow long stems/branches that don't fit my indoor model. Eventually, the plants will be growing so many branches simultaneously that they haven't the energy to "grow for height" especially if pot size (root development) is reasonably constrained. Internodal length often becomes progressively shorter allowing subsequent topping to keep the plant progressively lower.
Another way to use topping is slow foliage growth indoors for space while facilitating root development. A plant started well in advance of the season can be grown to a reasonable size, then cut back significantly on the main stem. If the containers are stepped up, the roots will develop and you may end up with a plant with well-developed roots for transplant outdoors, but that still fits conveniently into limitations of an indoor grow. Those roots will be better prepared to quickly develop the multiple branches encouraged by topping and you may be in a better position sooner outside than otherwise. This wouldn't necessary mean the plant was further along from time of sprouting, but it might be a way to have more rapid development subsequent to moving it outside when indoor space is limited.
Just some thoughts to consider. There are many reasons to consider topping and different varieties respond differently. Generally though, I don't consider topping as a way to significantly increase production. I tend to think the best way is to start indoors at the right time, not too late or early, step pots up regularly so roots aren't constrained (not simply before root-bound, but well before root-bound), and getting the plant out with proper hardening off after the cold snaps that might stunt it. Good media, proper water, adequate feeding. IMO, there aren't many (any) quick-fix gimmicks that are going to result in significantly better production than doing a great job with the basics.
EDIT: Wow, that post became a book fast!