I really wish we’d get an email when there’s activity on this thread, as with most forums. Otherwise i wouldn’t think to bookmark it and check back – which is why i forgot about this until now.
The problem occurs with and without caching. As far as i can tell it always makes the same changes to the menu.
Don’t think i can give you backend access to this site, at least not without some discussion with the client, so maybe i’ll try to debug your code and narrow down the problem.