HumorSpren

@Darnam I agree with this, isn't this separate "pool" of power also burned to release its power? Or at least that its power is expressed allomantically. All the enhancement metals are released in a flash (no aluminium or duralamin left over and I assume, no nicrosil or chromium). I posit that it would be impossible to store this energy feruchemically and you would thus be unable to start a compounding loop. I agree that it just because something is ridiculous, it doesn't mean it can't happen, but this logical (to my mind, at least) explanation would remove the danger of "story-breaking" or just plain difficult to conceptualise powers. I do not think it is a coincidence that all of the more esoteric powers (luck, identity, investiture and to a lesser extent, connection) are connected to the "one-and-done" enhancement powers.

I don't think it's possible to compound any of the enhancement metals; burning them just sort of, uses them up. It does remove some of the more nonsensical combinations. Infinite investiture would certainly be ridiculous.