People have done this with Matroska playlists already for some series, although it's not always worth the amount of work that gets put into it. (For example, the opening might change from episode to episode so that spoiler characters aren't shown before they show up in the series.)
Or still shown after they are no longer on the show. I've considered cutting my videos to exclude the intro but it's not an exact science and sometimes the intro is different and I don't want to miss that. In the end most intros are not long enough to worry about cutting (though GoT is LONG). If it's long I can just FF through.
