I’ll chime in, since not only did I work down the street from Concord De La Salle, but my former co-worker’s son is an alum.
Concord is a mixed area: some very affluent, some trailer park/hella sketchy after dark. De La Dale’s success came from a great system. Ladouceur recruited all over Northern CA & got guys who wouldn’t normally been afforded an opportunity to attend such a prestigious private school, a chance. Once he got his players, he built systems around each player’s strengths, both on defense & offense.
The team start taking a hit on talent as tuitions rose in price (if I’m not mistaken, my co-worker said he spent a little over $80k on his son over 4 yrs) & neighboring schools began to become more inclined to keep their top players home. Once Ladouceur retired, the program wasn’t the same. The infrastructure is not what it once was. They still produce top tier students, but the caliber of athlete is not the same as they once was.