Hi all
Len Lehman here - past chair of Alleghany Chapter, North American Rock Garden Society.
Most people use Reginald Farrers Book "The English Rock Garden" as a standard reference for what a rock garden is and is not.
He was most emphatic on how rocks were placed and his most famous quote involved haing rocks pointed upright. His quote was "A rock garden should not look like a mouse's graveyard!" Czeck rock gardeners consider rocks like a tiara with alpine plants as the jewel in the tiara. A modern trend is toward crevice gardens!