Where did it say that? MSV could be cleared in full 463 blues correct, but the hc modes needed at least half ur gear in the 489 normal's to clear full hc. The main boss tier ppl have used VP upgrades on HC gear is Terrace as its the hardest one to clear.
I never said heroics were tuned for 463, but the majority of people needing the "nerf" are those stuck in normal mode. the point I made was it brought your ilevel close to the loot dropped from heroic if you upgraded normal gear, meaning the point was you could get further in normal as you were basically using gear close to the reward for killing heroic.
so the point is it was a nerf as you could go more or less to the next gear level up. so if you started with LFR gear you could bring it close to normal gear drops, then if you got the normal gear you could bring it close to the drop for heroic mode.
so 436 was what the dungeons were tuned for in "normal" mode, this is why I said it makes you out gear it even more as you can upgrade gear to close to the same level as the reward from the tier above. meaning it is obviously massively more than you actually need to kill it.