Kiiwa and those: Not all overmapping is bad to the same extent. I believe Kiiwa's point is that tutuhaha used overmapping in a way that was still reasonable and people found playable, and those's point is a general point against overmapping, that if you overmap to an extreme then it's not playable or fun.
Now, I think Kiiwa's response is a bit harshly worded, but I agree with her point that you can use overmapping to a certain extent without it becoming unplayable. You can see an example of unplayable overmapping in those's post, but it's not relevant to the extent of overmapping found in this map.
Like any mapping technique, you can use just some overmapping, or you can go too far. If I'm using new combo spam as a mapping technique, it can be done reasonably (
example) or not (
example). Overmapping is not inherently bad, but it is often done badly which is why people tend to draw that conclusion. As it pertains to this map, it's a question of whether it's being done reasonably or not, and in my opinion yes, it is and there wasn't a need to unrank it for that reason.