I planted a SFG this year also, and put WAY TOO much stuff in it, I am going to find out how it does, but, at harvest time, I will let you know how my tomatoes fared, needless to say, I planted more than 1 per sq foot. ( umm, didn't read the web site, just looked at the pictures... ).
I am trying to tie up my cabbage leaves because they are so big and I am also tying my potatoes and sunflowers together so some of their neighbors can get some light, I just want to mention, my garden right now looks terrific! But, I think it is REALLY going to be crowded later this summer.