It may be hard to you, but we killed every boss on heroic bar putricide and sindra without a buff, then later did them without a buff. We killed LK heroic with the buff, but he is tuned around it (no guild has beaten him without at least 5%).
Sunwell was infinetly harder than ICC 25 HC. Infinetely. It only seems hard to some now, because they couldn't even get to Sunwell in TBC. The end game is easier than it was at the end of TBC. Again you are talking about things you don't understand.
Not that it matters, but I wasn't carried. I've raided every boss since Vanilla, and for anyone serious about raiding, wrath has been a huge disappointment.