dungeon gear (mixed with a spot of valor gear
To my understanding (at least the first raiding tier) is tuned to be done in heroic dungeon gear (mixed with a spot of valor gear, unless valor gear goes away, or something). Once you have pretty much full normal gear from the first tier, you're adequately geared for the second, and so on. The 'trouble' comes in when you're playing catch-up, and I refuse to believe that you *need* Flex gear even now to conquer normal modes.wow po This is just players being asinine about gear requirements. As demonstrated in WotLK, really good players can go very, very far on limited gear (people in perfectly optimized blues were killing bosses up through ICC-25). While the same experiment today might not meet with as much success, the principle still stands: good players don't need great gear to conquer encounters.
For illustration, here is the iLevel - Content chart for MoP:
