Inside Ballast

Jim Michalak has a design (Picara) with 500 pounds of steel plates as ballast.   This seems an elegant way to combine very shallow draft with stability.

Per step 23 of the plans, "Ballast, about 500 lbs, from eight
steel plates 6" x 1 1/2" by 24" or equal. These are
secured to the bulkheads with metal angles." Inside, with
the bars oriented for and aft, with an angle fastened to
each of the two bulkheads (which are 24" apart) running over
the ends of the bars to keep them in place.

Does anyone have experience with such a scheme?

See also http://www.duckworksmagazine.com/04/s/projects/picara2/index.htm