I have read just about every DIY article on this subject including the one you posted, there may be some merit to the idea, but it does sound like a lot of hastle. If you don't get the drip rate right, you could kill everything in your tank. I think a DSB is definitely the way to go if you want to reduce the level of nitrates in your tank, and the beauty of a DSB is the less you mess with it, the better it works.