And you know what? I did.
Despite some frustrating hiccups during the preparation and assembly, the overall result was stunning, if I may say so myself. (Because I am, and will continue to do so. I was, and am, immensely pleased for having done this.)
The mushrooms did end up looking how I imagined, but they were by far the most troublesome pieces of this whole adventure. I live in Washington, where it is nearly always damp, which is the enemy of good meringues. They constantly fell apart, or started going gooey, and the tops kept sliding off the bottoms, despite the little ganache glue I used to keep them together. But honestly, they looked nice for the pictures, and that was all that mattered.
It was a perfect Christmas dessert, and we enjoyed it in front of a roaring fire with glasses of champagne. When I asked Reid if he would rather have had real cake, he said no, and that he would choose crepes over cake every time.
So here is to a project I can be proud of, one I wasn't sure I could pull off, but did. And here is to already thinking about next year's. Cheers!