Anne Rice did for one of her later books, and it did not do as well, as her previous work. A good development editor will not tell you to change major plot lines, but will make suggestions about tightening scenes, characters, errors in plot lines even the flow of the manuscript. They will spot the holes you have missed and make you look again at your story. With a good editor you have two way conversation about each. But a good editor does not come cheap if you are self publishing, and I think if you are, and you can afford it, do it. Also a copy editor is a must for self publishing. It will put you head and shoulders above the rest.
As to Stephen King's the Stand, huge chunks were removed when it was first published. A couple of characters had their roles in the original book greatly reduced, some were cut out completely, and reference to one female character's sexuality was not completely removed, but if you blink you would miss it, also her part in the story was greatly reduced. Some people prefer the original publication, as the story is tighter (strange saying that for about such a long book lol) and in their opinion the original manuscript waffles on too much. Others prefer the extra detail in the original manuscript. (I believe a number of King's books have now been published in both originally published, and expanded versions. Bit like directors' cuts with films.)
As for me, personally, I found the editing of both my books helped me focus on what was necessary to tell the story, and reined in my tendency to put too much detail in where it wasn't really needed.