While I don't define meat cuts from a contest organization list of rules (they're grouping them for their purposes), I'm talking about learning to cook ribs so we can figure out why loins and bb don't cook in the same length of time.
You say tomato, I say potato... I did say "technically", as in the meat cutters guide it's the same rib, just trimmed of the loin (hence smaller and less meat)
Loin/Baby is like saying Spares/St.Louis, just two different cuts of the same ribs.
Full spares (untrimmed) will take longer than trimmed
Loin (if true loin, over 3) will take longer than baby backs
Here's the key. Know the cut and weight of each rack. Loins will be heaving, full spares will be heavier.
Oh, and just for reference, baby back was a marketing term by the Danish Gov't to sell us undersized ribs and we "bought" it.
But back to the original question
I think the reason most hang ribs is that they like the "way" they cook. More even heat and smoke is usually the theory.
I smoke mine on the rack, but I flip them (don't like the grill marks to sink into the meat)
I think just a little experimentation would give you the results you want. Keep an eye on weight and you'll improve your ribs.
Smokin (owner and sole proprietor of the Original "Smokin" post for length and detail)