Edit: Quick search turned up this article about the jumbled-word phenomenon, containing the example text at the top: https://observer.com/2017/03/chunking-typoglycemia-brain-con...
He didn't use those terms but adopting them from this thread - I learned that day that these really are two distinct modes.
They cannot be completely interchangeable:
“There are white people among us: i.e. me and my father” is totally different from “…: e.g. me and my father”.
A less common word like "phoenitic" or "subvocalizing" is read as you say. However by the end of the sentence we know how to read "phoneme" because we encountered it 3 times in one form or the other.
How?
They don't mean the same thing.