Well instead of pure, put noble,or honorable.
If anyone needs proof of how A/JLA was full of checks and balances then they haven't read the comic. The sole reason that the first crossover was scrapped was because of Marvel and DC bickering over who would lose to who. Neither company wanted their heroes to get beaten...which was understandable.
So Busiek wrote the only story he could: one where for every loss, there was also a victory (even if they were small).
Examples:
Thor lost to Superman (due to PIS), but Superman couldn't lift his hammer. Thor later also hinted that he would beat Supes in a rematch.
Photon got worked by GL, but later she learned from the last fight, and took him down.
Flash was too fast for Pietro in the DCU, but when he went to Marvel Earth he lost his speed advantage.
She Hulk was curbstomping Aquaman, but he used his wits to outsmart her.
Batman admitted that Cap might be able to beat him...might. So that way the companies top street level heroes didn't lose any face.
There are more from where that came from, but I need to read thru the series again to get the specifics.
Still, A/JLA is canon--at least in the DCU. I think Supes wasn't able to lift Mjolnir because of what the Grandmaster did to he and Cap.