today finnaly completed in heroic mode with 5 paladins.
in waves room i found better tactic, at lest for me and for a full pala group: i stay in middle, have wrote a simple macro like /target mob(by name) /cast repentance for all 4 retri pala. so i can CC 4 mobs : now it is (almost) a simple single target-chain fight.
boss 1 is annoying with his fear spell.
final event: i hide the whole group in the sides (where is rocks ofc) so i stay hidden.
mobs come to me, i turn away from group the big mobs and attack casters.
casters are really dangerous for melee coz they can stop themselves too far away.
often i wiped coz cant attack them if Lich King reach their position.
with current mobs huge movement( you noticed?), tanking them is not exactly easy: hope blizzard fix it soon.
just today i wiped 7/8 times before do this final part.
heroic Icc 5 men all cleared