How can I avoid overuse of words like "however" and "therefore" in academic writing?
Let me suggest an alternate view. This is in regard to writing proofs and other very technical things. You want, above all, for your intent to be clear. It may be that &quot;however&quot; and &quot;therefore&quot; are the best available words and that they clearly express the flow of the argument.
After all, if you were writing the proof purely symbolically you would &quot;overuse&quot; certain logic symbols in order to be exact.
And, don't let &quot;fancy words&quot; get in the way of your readers deep dive into the ideas themselves. Sometimes the most obvious word is the one that is most quickly understood to express your intent. This might be especially important for those who know your subject, but are not native speakers of your language.
OTOH, I haven't actually seen your prose. If an editor or reviewer objects, then you can change it to suit, of course.