I was thinking about the new patch and how it breaks mods like decursive and auto heal cancel. I understand that the change to SpellStopCasting() makes mods unable to cancel heals without player input. However, what stops mods from targetting people that get debuffs on them and then having the player spam one button (input) to cast cleanse?

I'm not arguing the changes, and I think they're a step in the right direction in terms of mods completely taking over end-game raiding, just curious as to what makes it impossible.

Unless I'm mistaken, I don't think decursive is broken in 1.10

Every patch people assume that decursive is being broken but they haven't actually done it.

When Blizz UI is reporting mod for "bad behavior", it isnt always correctly points to the addon that is doing it.
If you have an idea how addons work - they hook some standart function. When more than one addon hooks same function, this creates a hook chain. And Blizz UI is always blaming last addon in hook chain.
Plus its not only SpellStopSpellcasting is changed, hooking to movement keys and functions is not allowed to 1.10. Thus ppl that bounded decursive to movement keys will see this message.

I enjoy the "OMG I CAN'T BELIEVE BLIZZARD BROKE SO-AND-SO MOD!" threads on every new test server. :)

It would be pretty difficult to break decursive, since it uses pretty basic scripting functionality. They know they can't break it without breaking many, many other things, so they won't. They're just not designing Lucifron-type encounters anymore.

Cool, I read about decursive being broken in quite a few places so I assumed there was truth behind it. Thanks for the responses. :D