There is likely a prospective conflict with this, as this is the internet and we all love to blame others what goes wrong. For if 272 ilevel is bad for this dungeon, for the most part, yes it is, but I would need to see your specific gear layout to comment, because having higher ilevel on the left is a big difference then having it on the right side.
For the "I am a veteran of this game and i know how to play and whats fair and whats not " Well.... I see this a lot.. by people who could learn more about the game so I am not so sure about that. I would think a person that knows what is truly fair would prepare for this dungeon better. You have to understand people habit and the thing is healing in this game is "easy" and not much to do, so when you have a healer with such a mind set, more so with a healer thinking they know everything and can apply the same rule set to these dungeons would only be asking for trouble. They could have the exact mindset as you, feeling they shouldn't have to heal as much as they needed for you. Same applies to the 2 dps freeing the healer thing. A solo, DPS that knows rotations that has fitting gear would cut though it fast, and if one is near it while the other is far (and melee) would kill it before the other has the ability to reach it physically. Most of the time 2 dps can move to the other's hand and kill them fast so they can move to the middle one in a speedy manner. Some people have issues adjusting on the fly when something does not fit what is expected, again humans tend to fall in a habit, and skill in this game comes from knowing how to adjust, and in the average dungeon run, it is not going to be commonly seen.
Also being captured on the final boss during those hand phase things means it is being done wrong to begin with so =/
Basically everyone had a fault for this situation and they wanted to shift the blame on you more then it should have, something that is common on the internet in general so =/ typical average DF experience? We got a mega thread for such things here. End of the day you should be geared better, they should done mechanics better, everyone has a fault here, and they just wanted blame shift more on you, all it is.