I looked into this, because I thought I had mucked about with this years ago.
Close is putting files back on the MRU, but not forcing them to the top or forcing them onto the "top-9" part of the history menu, so they get plugged into the sorted list under "More Files", which isn't as useful for those purposes.
I am going to file a feature request for adding the "reopen-recently-closed-file" command, maybe have it track the last N files. Each invocation would re-open one item off of the list. Guess it could also have an "all" argument to reopen all the files in the MRU history.
I am also going to file a feature request to add an option for close to plug filenames into the "top-9". It is going to have to be off by default.