I hate to correct you, but here goes:
Lindgren did indeed run 13:44 flat on a dirt (clay) track in Compton in June 1964. He led most of the race before being overtaken by 2-mile World Record Holder and Olympic Gold Medalist Bob Schul. Lindgren ran just 9 seconds off the current World Record.
The competition was admittedly not very deep at the time, but up front it was incredible. Ron Clarke? Peter Snell? Jim Beatty? Bruce Kidd? Gaston Roelants? Do these names ring a bell? Legends all of them. Lindgren was at his best at a time when the distance records in track were being smashed and rewritten by the greats.
Before Lindgren and Ryun came on scene, things weren't too impressive in America but they came in right at the zeitgeist. Remember, it was this year - 1964 - that Americans were the best they ever were at the Olympics. Gold medals in the 5k and 10k. Bronze in the 5k too. And Top 5 finishes in the 800 and 1500.
When Lindgren ran 13:44 in high school, the previous high school record was 14:58! Think about that. And that was by ensuing NCAA Champ Dale Story.
Lindgren ran in an Olympic exhibition 6k cross country race at Mt. Sac one month before the Olympics in 1964. In the field were Billy Mills and Bob Schul. Lindgren won the race by a landslide. Ritz would NOT have beaten him in a xc race in HS. No way, no how.
By the way, all of Ryun's records have been broken too. But both Lindgren's and Ryun's records lasted 40 years or so. And I don't count Lindgren's indoor 2-mile record as being broken anyway. Lindgren was 17 when he ran 8:40 flat on a 176 yard wooden track. Cheserek ran less than a second faster but on a 219 yard modern track - at age 19!
Lindgren still holds the high school record officially for 3-miles at 13:17 flat, run on a dirt track in Jamaica the same weekend as running a 4:01 mile at the same meet.
....I could go on.