@Jim - I've read this twice and I still don't understand what it is you are doing
However to answer your last question in the post, yes it does sound like an ugly hack.
You should never have a need to be fiddling with the title field in calibre, encouraging people to do so will then break numerous other plugins like metadata download, find duplicates etc.
Since I don't get what you are hoping to achieve I don't know if this is the correct solution for you, but have you looked into
metadata plugboards? You don't mention them in your post. They are the "proper" way to manipulate titles when sending to the device without changing them in calibre.