I posted "When Following Through Sucks" on my personal Facebook page, and some friends suggested that the kiddo might have sensory issues. I think that may be the case (I know I did when I was little!), but I'm wondering why they just popped up recently. The leggings and tights in question are the correct size, and once she has them on, they do not appear too small at all. However, that being said, by nature both leggings and tights are supposed to be snug fitting; they are not pants, after all.
One friend suggested that giving away her dresses and jumpers might be interpreted as a punishment; that is not my intention. I really can't let her wear dresses or jumpers in winter without some covering on her legs, but I am willing to put them aside and let her wear them as play clothes if she won't wear leggings or tights with them. Two have already been put in the pajama drawer to be worn as nightgowns (fine in my book, since they are showing signs of wear), so hopefully this won't be too traumatic.
There are several books in my library that mention sensory issues: The Highly Sensitive Person (I think) and Raising Your Spirited Child, so I do have references to consult if she really is starting to suffer from this problem. However, the screaming and fussing and whining are not OK.