I'm a guy who believes in completeness. If I chart a song, I chart all the parts, and add all the 'bonus' to it (DD, sections, etc). I think approved songs should be as such. I want my song to be indistinguishable from official DLC, and I believe providing options is a good thing. It's easy to add DD to a song, and I like the level markers in it.
I've also added non DD bonus arrangements for the DD rage crowd. Again, I believe in options.
I chart songs I can't play because I want to learn how to play them. You don't necessarily have to be able to play them to ensure the chart is right.
As a side note, it's cool to be passionate, but lets keep it civil in here, peeps. Everyone should be entitled to their own opinion without hostility. It's getting a little heated and it's easy for things to boil over.