My old person trait is that I think 'ghosting' is completely unacceptable and you owe the other person a face-to-face conversation.
It has the advantage of distinguishing abbreviations (e.g. "e.g.", "i.e.") from sentence stops, so that's why the GNU coding standards recommend using two spaces in code comments, to allow emacs to be able to properly detect sentences and correctly use commands like (backward-sentence, forward-sentence and kill-sentence)