Wow! That is really close spacing, but I think those are recommendations for market growers that probably only care about the main head. The NCSU article says:
Central heads will vary in size, depending on variety, spacing and growing conditions. The central head weights will range from 0.3 to 1.0 lb each, while side shoots will average between 0.1 to 0.3 lb. The commercial trade only accepts 2 to 5 heads in a 1.25- to 1.5-lb bunch. Under good management and good growing conditions, per-acre yields should average between 400 to 500 cartons (21 lb net).
Note my bolded sentence - assuming good fertility and wider spacing, you should produce much larger central heads in a home garden. Here in the north, my central heads go over 1 lb, and I get enough side shoots after the main head is removed so that I only need to plant once in the spring. But after a time, the side sprouts re-grow too small for a commercial grower to bother with, though they freeze just fine for me. I try to visualize how large the plant will get when I plant my seedlings. Even at my roughly 12-15" spacing, the plants overlap when they are grown.
I wish I could have seen the Clemson pdf, but it downloaded so slowly that I gave up on it.
__________________
Dee
**************
|