Agreed. It's realistic to expect something to POSSIBLY get rejected but I don't think it's a good idea to expect it. Just have a "wait and see" attitude and, meanwhile, just keep submitting everything else everywhere else.
But if you're talking about sending chapters of a book to publishers, you need to be sure and let the others know it's a simultaneous sub. Though you probably already KNOW this!
Sometimes we have to wait so godforsakenly LONG to hear back on book submissions it can be hard to understand why some publishers frown on simultaneous subs. Can't WE be the ones to decide which pub to go with in the event we get back two or three acceptances? You know, that in itself is a nice thought.
Good luck to you!