Is this possible? Layers

Is it possible to have a document with two masters; Light and Bold. Then on each master have an extra layer with a decorative element.

Upon export, I would like to export one font with the normal layer and another font with the extra layer added.

So for instance, the “normal” version is just an A, and the other version (with the extra layer added) has the A plus an extra element.

Is this just wishful thinking, or is it in fact working?

I would insert the decorative element as a component, and the Remove Glyphs custom parameter (to delete the original deco glyph) for the instances without the element.

You are so clever. This is super! Thanks!