How does the 'Fusion of Elements' talent work?

[Rotmist-area-52]

Fusion of Elements

It says “the next time you cast a Nature and a Fire spell”, but it seems like the only thing that procs this extra ele blast is a flame shock. After I cast Icefury, I can cast lightning bolts and lava bursts all day and I get zero ele blast proc, but right when I cast flame shock it procs.

Is it bugged or am I interpreting it wrong somehow?

Edit: Just found this referenced here as well

Does lava burst not trigger fusion of elements?

I have the fusion of elements talent where it says after casting ice fury, the next fire and nature spell will cast elemental blast. After casting a nature spell, casting lava burst does not trigger elemental blast. I have to cast fire shock in order to trigger it. Last time i checked, lava burst is also a fire spell? What is going on?

[Goomdar-dalaran]

Nah it works as intended. The talent requires you to cast a nature and fire spell. But since flame shock does volcanic damage which is both fire and nature damage it procs it instantly compared to simply casting lightning bolt and lava burst together

Edit: Casting elemental blast also procs it instantly as well because it’s elemental damage so it does include nature and fire, as well as the other schools

[Favi-burning-blade (Favi)]

I imagine, it was meant to be the DF season 3 set bonus carry over, which provided an Elemental Blast at 60% power when casting Primordial Wave. Obviously, this involves more conditions, but it also includes a more triggers. In addition to Primordial Wave, Elemental Blast and Flame Shock are included.

I wish this would interact more with our talents. Namely, Surge of Power.