It still depends on the skill of people, but it does make it more forgiving. I was going through Garuda HM, Titan HM, Ultima HM and Mogry HM and overall the echo did definitely help. For example Titan HM became doable @5 stacks with the 6 people that had the necessary skill/latency (yes, basically from the 1 minute point 2 of our DDs would fall from the platform nearly each try^^).

It also helped us survive aoe damage longer, lessens the strain on heal if the tank is a bit undergeared etc.

I'll give you that it's by no means a cakewalk, at least the core of the group needs to know what they're doing.