I think Aggron should stay on the list. Sure it isn't used much, but that doesn't necessarily mean that its a bad Pokemon. It's one of the few viable Steel-types in the tier and a recoil-less Head Smash means its no slouch offensively. It is a bit like Steelix in that they both have large Defense but horrid Special Defense, and besides it's already written so I don't see the use if its taken down.
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