I think it’s fair to say that 9.68, 9.77(AR), and 19.86 did not come from a mini-peak. Wariner may have come to the trials not yet in peak form (or maybe he screwed up the race plan like they said) , but if Doc Patton tried that, he wouldn’t make the team.
It’s a little different for the distance runners where there aren’t so many quality athletes (Lagat probably not near peak form yet), but it’s also possible that Khadevis Robinson tried that and it cost him a place on the team.
When the wind is positive for 100m, that’s bad for 400m, as it was the case during the US Trials. Headwind in the first straight didn’t allowed faster 400m times.