Theoretically setting the Text semantic should mark a file as the location to first open to, I don't know which ereaders will support it however. The Kindle definitely does (although as DiapDealer pointed out, KDP seeems to arbitrarily change that, sometimes, when uploading).
@
Hitch claims to have found a fix for that, but since her job is to process and polish peoples' ebooks, I don't blame her for refusing to share a trade secret.
@
Diap -- I'm afraid I don't quite undertand your "micro-manage" accusation...