Thanks! Conceptually I thought it was quite similar to how Beginner’s Luck effects obstacle.
There is of course, now I think on it, the flipside way of doing it. Give a flat (let’s just say +1) Ob modifier for the Effect, and then double the Ob increases from breadth and duration modifiers.
I think that actually gives a more “elegant” self-directed progression for Forming: When you’re learning the Effect, you have to stick to the shorter, narrower expressions until you’ve Formed the Effect.
Hmm. I will consider.