not 252 HP EVs. I said take all of the SDef EVs and the same number from Def. This still leaves some in defense to help counter some physical moves (I didn't say the exact number to help retain the semi-secrecy of the set).
Edit: I redid the calculations just to double check and I found I misread something. it's a 20%chance to survive an uninvested close combat from Infernape... it does reduce damage from all super effective moves I tried by almost 2-5% (not 25-30...) so I need to re work this a bit more. I must have received minimum damage when field testing it on PO earlier, which would explain why it seemed to work. it does increase the bulk of the substitutes though, just nowhere near as much as I thought... I'll tinker with it a bit more because I think I probably overshot the "golden number" for the HP/Def tradeoff, if there is one. The result of said tinkering revealed that the optimum damage resistance was when 36 EVs were taken from each defense stat and were given to HP. This means Politoed's Scald can only break the substitute about 30% of the time, provided sand is up (which it usually will be unless the toed runs a speed hindering nature). it's still only about 2.5% less damage for both Def and SDef, but it's still a little better than before.
