All due respect to Larsen, but NO WAY. Hall may have been doing harder workouts, but it was because he was pushing himself harder in the workouts.
I know Steve Ortiz and he ran 28:31 in the OT 10k in 1980 I believe (while in college). I don't know if he ran faster while in college at other events.
Ritz ran 14:13, 13:52 and 13:44 while trying all-out for the record. I believe he could have run ~28:30 based on all that we know about him while still in HS. Hall could not have. Hall could not beat Ritz on the track or XC.
If Ritz could run 13:44/~28:30 he still could not have run 2:10:59 in HS. Hell, it took him like 4 tries to run it as a PRO. No way could Hall have run 2:10:59. He had trouble finishing mile races where he went out too fast and ended up running 4:10.
If Hall and Ritz had been doped like the pros are now (with everything and whatever they have been using since 1993) in HS I believe they could have run 13:20 / 27:50 in HS (just look at how much the WRs dropped when EPO became widespread? WRs dropped 19.03 secs and 45.48 secs in 6 yrs after having leveled off after 30 yrs of steroid and blood doping use). At least Ritz could have.
And in that case, they could have run 2:10:XX. The first time an American ran under 2:10 on a course besides Boston was Salazar running 2:09:41 for first place at NYCM (and beating Bill Rodgers) after running 13:23 / 27:49 in early September in Europe. Just 9 weeks later he ran 2:09:41 there in his debut.
But at that point Salazar had run 13:22 / 28:06 in 1979 and 13:23 / 27:49 in 1980 as a junior and 4th-year in college. Ryan Hall was nowhere near that level as a HS senior.
I think all of the sane among us can agree on that.