Flash LibreBoot into ME, unlock all flash for writing?

When modding Z620 with @billdh2k, it emerged that it’s fairly easy to reflash ME region with anything, but the BIOS region is a bit harder due to the protections.

So this got me wondering - if anyone tried to flash a micro-BIOS (LibreBoot?) into the ME area, and then use that to flash the core BIOS region.

Is this even feasible in theory?