I already saw a Sergeant with ELO2000+
But the problem with ELO is that you can't go check it while you play, it usually takes about 3-4 mintes to load the page due to the high memory AOE3 takes, so usually the players ocmplain. And in team battles (3v3's mostly), it'll take forever to check up the ELO, so i don't think it's quite useful
PR is usually more useful, since it situates you in the margin of skill; you CAN'T be THAT bad if you're a Major; even if you suck like hell, you'll still be better than a Private. So if you play with a nooby major, just put him in pest list so next time he's on, you'll be sure to not play with him ;)

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