Not to forget that Mace Windu beat Sidious in a duel... but then the spoiled kid Anakin came and whined a bit and ruined everything...

If cant manage to keep yourself alive for 30 seconds after the boss enrages, then you are doing something wrong... because that's where your cooldown skills will help you win the fight. And in my opinion, the hardmodes are meant to be done after you get atleast some kind of an lvl50 gear from flashpoints/GTN/pvp or whereever you can. It isn't wrong in any kind that your group cant clear HM flashpoints with some lvl40-49 questing gear...