I don't know anything about re-twisting or going bald because of it or anything like that, so I can't say anything about it. But I dont get how it makes them look tidier? I mean, maybe I'm weird, but the picture SE often posts with his dreads, they look neat to me. Long, yes, but not untidy. Untidy dreads to me are just when they're not mature yet. My hair is untidy now, for sure, but when they're fully locked up, they won't be. Except for loose hairs, but they tend to be not as noticeable as the person with them thinks. So even if twisting doesn't cause any problems, there isn't really a point to it in my opinion, cos you get past the messiness and then it goes away.
That said, to answer your question as to why people here are against maintained dreads, it's not specifically because they're maintained, but because the methods used to maintain them have evidence to suggest that they're at worst damaging, and at best useless. If there were ways to make them neat without any harm coming to them, people wouldn't be against them. They might disagree with the idea of making dreads neat and uniform, but they wouldn't be against people's personal choice of it.
updated by @tara-c: 07/23/15 04:43:31PM