I use a method similar to this and it works absolutely fantastic!
I have raised beds now, but I have used it using wide rows. My beds are 4' wide (the length doesn't matter) and I plant my seeds equa-distant...if beans are to be thinned down to 4" between plants and 18" between rows as stated on the packet, I plant them 4" apart in all directions. I do this with all my plants and I have never had a bit of problems. It makes it easy to customize your beds (some want more acid or more alkaline soil), you can almost eliminate weeding once the plants are up a bit (they shade out most weeds), and the soil doesn't get compacted from walking on it. I think it also makes it easy to harvest and repeat sow (follow one crop with another).
It can be a bit hard to do with things like squash and cukes because of how much space they take up, but if you can trellis the cukes, it works the same.