If I book a domestic flight from LBA to MAN via LHR will my luggage end up at MAN with me? Its easier and quicker for me to fly in to MAN for my flight to MCO the next day, plus some extra tier points : )
So you're going to fly LBA-LHR, then LHR-MAN?
If you book luggage then and there is plenty of time in your connections, then yes, your luggage will end up with you in MAN.
You say it's quicker to do that, I assume you mean quicker than walking as otherwise surely train or car is the quickest way.