"Just from observation the Lycoming engine appears to be "4 banks of nine cylinders". Happy to be proved wrong though."
I think it's just the way they're looking at it. Where we're used to saying "2 rows of 9 cylinders," sectioning fore to aft along the crank, they're looking at it like 9 straight fours on a common crank, breaking it up every 40 degrees into a head for 4 cylinders. Is there a definition of "banks?"