[Jeff Kropp]

... try to look carefully at your plants and note the biomass also in the tank.

I think that plant mass in a tank is a key issue when considering lean tanks. If you are striving for rich, lush, luxuriant and dense growth trying to stay lean may be counter productive. However, if you want unplanted open sand and a sparse natural look then lean is probably better. I have never dosed my tank to 10 ppm NO3 and have had some nice looking and very stable tanks to show for it. I have had trouble when I wanted an overgrown super lush look; and I have found that the leaner I go the more likely I am to have problems with a particular species of plant failing when my species selection is diverse. Rich dosing, as commonly associated with the estimative index, assumes a desire for bursting lush growth and super diverse species selection with minimal troubleshooting.

Although light limitation can serve to create a lower maintainance tank, a lean tank doesn't necessarily require less light. I think your just enough, just in time, with minimal water changes is an interesting project. Go for it and let us know what you learn.
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Jeff