I think this change is both a good and bad change.
I really like how things such as Kalecgos and Vicidius are able to be done, but I hope they don't nerf other fights which are possible (albeit quite hard) in the process. Personally I wouldn't mind a list of the changes to see how many things are actually affected by this and to what extent the nerfs will be.
Reliquary for example is solo-able right now due to me being a ret paladin but i can understand how it being impossible for some other classes is irritating to them. Definitely something i'll be checking come the patch to see if these changes are to make everything easily killed by every class or just to stop the impossible.