"There is no discernable temporal pattern that marks a word as no longer a loanword. It's a specious sugestion, and, most importantly, it won't help anyone spell plurals of < o >-final words any better."

This kind of error arises from mistaken thinking about orthography.

Also? This doesn't just happen with bound base elements! That is just total nonsense. A replaceable <e> can happen on free or bound bases, as well as on suffixes, and so can a potential <e>.