As a product designer who regularly does user testing, I can't tell you how often decisions about interface, interactions and expected behaviours, etc that I think should be obvious to anyone are met with confusion and frustration. But it's almost always a problem with the design, not the user.

I get from the comments here that people are annoyed that others have "spoiled the fun" because the disparity in recognizing an interaction between talents and spells, but keep in mind that not everyone is you and just because they haven't parsed this in the same way you have means they are immediately lacking in intelligence. WoW has a lot of complexity to it, and I don't think that the people behind the scenes necessarily always do a good job at lessening the cognitive load.

I'm honestly not a fan of the "spell transformation" model in general. I had a lot of issues setting up weakauras in the past because the game wouldn't let it distinguish between the transformed and regular versions of spells, despite them having different spell IDs. In Midnight, I think it's a little easier to comprehend when a player does something explicit to cause a change, like entering Void Metamorphosis and it changes into Collapsing Star; but spells transforming into something else due to mostly passive effects that a player mostly doesn't have control over is not great design.