I've done it in mostly columi, with a PuG group in mostly columi.. and it's acceptable content for that gear level, nobody was too squishy or hitting enrages and only one wipe.
Well I did not pick them out did I?
I am not saying it is not possible, my guild had me in there my second operation as a watchman and I did HM LI before I even finished my class mission. So I know anyone learn to do either, but I had the benefit of doing SM EC and HM LI over and over on a sawbones and a shadow. So I knew both very well.
No, if I pick 7 people to prove my point they will be 7 mains that have never been there. I am evil like that.