I'm not really concerned with negativity as much as thundering silence. If some people are getting something from this I'm happy to do it. I don't know that anyone has applied anything I've discussed here, though.
I can understand where you're coming from. However, I think there are several things at work: for one, I think a lot of people with experience would never take on the job, knowing just how difficult it is. The complete beginners may not have enough knowledge to be able to make sense out of what you're saying. It's a problem I often run into when I'm trying to trouble shoot computers with the help of someone who's an expert: they may be explaining something in the simplest, clearest terms they can come up with, but what they're saying makes no sense because I just don't have the background to make sense of it. It's only after we've backed up to a new starting place that I can catch up.
What I'm driving at is unless someone has a formal education, either from college or the school of hard knocks, the information you're passing along in an attempt to prevent certain mistakes won't help until the mistakes have been made. Someone may realize that a scene or sequence didn't work, but only then will what you're saying be of any use.
I'm sure a lot of people just give up in disgust when they realize the size of the job they've taken on and others get something finished (more or less) then swear off. The ones who decide to keep going and who are serious to want to learn and have a thick enough skin to face their own ignorance are going to be few and far between.