re: What defines the style of St. Louis and Memphis style ribs?

St Louis is a cut (trimmed spare ribs) and a style (wet). For many years, I use a modified version of a recipe for st louis style ribs. It starts with st louis cut spare ribs and consists of a dry rub (before cooking), a mop (while cooking), and a sauce (near the end of cooking).

Memphis is a style (dry).

JMO, lots of different opinions about bbq and not really worth arguing.