2. The next editor is the developmental or substantive editor. That person will probably be the same one who took the manuscript to the committee. This is what I call the broad-brush editor.
Occasionally, publishers contract with a celebrity or a newsworthy person who hasn't written a book. Unless they assign a ghostwriter, collaborator, or book doctor, the developmental editor helps that author define the concept, especially in nonfiction, and figure out, among other things, the target audience. The word I associate with them is flow. They help the author produce a logical manuscript that will attract readers.
Sometimes a contracted book, even by a well-published writer, requires substantial revision and restructuring. Someone compared those editors to therapists: They don’t tell you what to do; they get you to tell yourself. Some developmental editors, of course, do the restructuring themselves, but the most professional ones make it a learning experience for a writer.
No matter what the editor's title, you will see the suggested revisions. Most of them use track changes in Word. (If you don't know what they are and how they work, here's one of several links to explain): http://shaunakelly.com/word/sharing/howtrackchangesworks.html.
Unless you sell a manuscript for a flat fee, any reputable publishing house will send you the changes they make on your manuscript.
That also means it's truly a mutual arrangement. The editor suggests changes and you, as the author, have the right to reject or respond with a different wording.
A word of caution here. Editors aren't your adversaries and they try to make it the best product possible. Try not to be defensive. Read the changes and ask yourself, "Does this improve the manuscript?"
Remind yourself that once the book is printed, readers will think everything is your work.