Great info!
In you close up photo of the wedge and iron, it looks like some "stuff" is behind the iron. Are those shims or just an illusion I am seeing?
The heat treat is interesting. So you take it up to full hardness then draw that back a bit with some after-heat?
Do you have a specific hardness that you target (Goldilocks zone)?
Obviously you know what you are doing so very impressive!