@ Boilurn - Good for singles, wouldn't recommend it for doubles. No one uses Encore in doubles because the thing that got Encored will either switch its target or switch out, which isn't good for Politoed either way. And besides, it's too slow to use it effectively.
@ Adrian - If you can't get the HP IV, whatever. Trade for it or not, your call. But the Politoed MUST have the 252 HP. It's too frail not to have it (unless you're holding Wacan Berry but that's another story).