Originally Posted by
Tehterokkar
Patience, Flex raiding is just a step, mere test, rest assured that in Xpac 5 you can do norm/heroic with flex-mechanics.
OT: Blizzard has already made a few good changes to not make LFR feel a must for heroic mode raiders(be it you down 5, 10 or full clear in the tier).
The First change was that the Legendary quest line item drop rates were shared across difficulties in ToT, so if you did LFR the first thing on Tuesday/Wednesday morning, you wouldn't get any in the main raid in the evening.
Currently what they planned Flex iLvl to be, was about 535? Top end guilds will ingore it because it's released maybe 2 weeks after patch release(1 week of HC kills are done by top guilds) AND Heroic ToT gear is 543 or 549, that is, with 2/2 upgrades which you should have easily by now on all of your gear.
Dragon Soul was an exception, where people dropped their Heroic gear from Firelands in favor of the overpowered Tank set bonuses that each gave the raid a CD. But I see no set bonuses of this caliber coming.
TL;DR: Top end raiders already have better gear than LFR/Flex will drop.