So everyone is happy, now! ^__^
To be honest, I think the main problem in question #3 is that while there is a general conformity that says they can be together, it is how they are learned and what moves they can pair with that we are all disagreeing about.
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I have to agree with what Urza says about adaptability. There are some things that are "overpowered," but people adapt easily, kind of like Garchomp in DP or Snorlax in GSC. We'd get over it eventually, even if the Pokemon is "overpowered." I think that this is the main reason why we should be so careful with what goes on and what doesn't; so we can prevent the adapting to a theoretically overpowered something which could eventually lead to the breaking of the metagame without us knowing it, and by then it'll be too late to adjust because then people will just be uncomfortable with the change.
It's basically what we're seeing with Revenankh (with his combination of stat boosting and Shed Skin Rest), if that's a good comparison.
