Staggering palm is now not chaining

Staggering palm used to chain quite easily between packs. Post 0.5, this has stopped happening, significantly nerfing this ability. I thought hte patch notes said targetting had improved, but actually it has made it significantly worse.

I tried this on a new monk and my monk from the prior league. Both have seen this effect.

I suspect previously it would chain to enemies it could heavy stun instantly, and now it is only chaining if those enemies are already primed for stun (and can be stunned).....

Is this a bug or intended behaviour?