Don’t abandon your “legacy keywords” prematurely. Part of marketing is to convert people from the old ways to the new ways. If you are trying to establish a new industry then you are trying to introduce a ‘new way’ which is just another way of saying ‘new words’.
People will continue to search on the old words – the legacy words – for a very long time.
Legacy keywords should remain on your website and in your content; and they should always remain in your paid search campaigns as it costs you nothing to leave them there and it is a mighty valuable lead if someone clicks on it. (Remind your CEO of this when he or she goes on a rant.)
Think of it this way. If Matt Damon never appears in another “Bourne” movie, there will still be a significant number of people who search for movies in the franchise using his name for the foreseeable future. Don’t you want to find the real Matt Damon?