Hearthpwn

So I'm a bit salty. Apparently, sometime in the last month or less Sonya has been stealth hotfixed to now always only return a one mana minion to your hand, when previously if you had cost reduction effects on the board you could make some minions be returned for zero mana.

Now it seems that at least one of my OTKs, particularly the one in my sig, is now dead due to this hotfix. Is it intended to not interact with cost reduction, and when/why was this change made?

Found the April 16th hotfix which seems to have caused this interaction.

"Resolved an issue where copies of transforming Worgen cards with different mana costs would change those costs when they transformed (Splintergraft copies, Sonya Shadowdancer copies, etc)"

However, this new interaction does not seem correct. The hotfix seems to have meant to only target things like shifting stats of things like the new worgen cards, not completely remove legitimate cost reduction auras, like Mech Warpers reducing copies of mech minions in hand. 

This new interaction seems to be inconsistent with cost reduction effects of things like Naga + Giants.

Have I interpreted this incorrectly?

 The same hotfix changed how Splintergraft worked with Aviana.  The minions created will cost 10 not 0 now.