Hi Ennie! Thanks a million for sharing the SqFt manual. My husband and I were thinking of implementing this method in his parents' garden - though I'm not sure we're going to create raised beds (it's not a long-term investment for us: we're trying to secure a bigger plot somewhere closer to home, hopefully soon), but we have marked out the four squares and we're going to replace the current wooden planks with stone walkways between the plots. At the moment we're waiting for green manure to finish doing its job. You may see the pictures on his profile here on GtP (his name is Raffaello Bisso).
We were thinking of combining this with a rotation of plants that use P, N and K, plus "builders". I don't know if you're familiar with this technique. My in-laws' garden is in a cool area in the hills, therefore annual rotation makes sense. Where I live, right on the Mediterranean sea, I'm trying to keep my plots occupied year-round and I'm also experimenting with permaculture, which - I think - is incompatible with the fourfold rotation P-N-K-B. The fourfold rotation is probably more compatible with the GtP's growing tips than the syergic/permaculture approach. Just my guess, but I'd love to hear more on this from other Growers.
As I said, we're mostly experimenting with new techniques at this stage, so I'd be interested in hearing more about what you are planning to grow etc., and to keep in touch as our work progresses. Where are you based? (what climate zone?)