I'll try to make my point a 3rd time. Distilled water is just water without nutrients (aka, water). Once you add nutrients, it's no longer called "distilled water".
This thread starts off by saying that "distilled water is bad". Right, so don't use "distilled water" (aka water without stuff in it), use "nutrient rich water" (aka water with stuff in it)! Of course using pure distilled water in a DWC is bad. You've gotta mix it with stuff first, then it's no longer distilled water!
Those nutrients you add ARE the buffer. Yes, you have to mix the nutrients SLIGHTLY different, but not really.
The main buffer in a hydroponic reservoir is phosphates.
My point is that water is water! It's not like starting with pure water inherently ruins your grow op, you just have to change what you put in it slightly. Where water comes from is not important if it ends up as an equivalent solution in the end.
This is basically what my point was when i was saying to grow in nutrient rich water, not pure/distilled water. My point was that you must eventually put "stuff" in it, so it doesn't matter that distilled starts with 0 buffering.