I have similar production and short node-spacing on some of mine as well. I think that it has to do with not going fertilize/nitrogen crazy as well. In the spring, if the green growth is so explosive, there will be longer space, more stem and foliage growth and less fruit. Good sun exposure and not over watering will aid in this too.
I can also attest to fertilizing naturally. All I do is top-dress with a rich compost so that the plants don't just get the salt and chemical based N-P-K but a better quality, along with other micronutrients and microbials. Makes all the difference. Since it is at the top and not mixed in, the plants never get burned. It trickles down slowly to the root zone from watering, and the more you water (hottest months) the more nutrients the plant gets, so its the perfect solution for me year-round. If you have a few worms in the pots, its a plus, because they come up to feed and bring it down to the root zone through their digestive track which is one of the best, most bioavailable forms...
Go figure -- what happens in nature works well. : )