Timo, 
If the word 'authentein' is only used once in the NT there would have to be debate about it's meaning.  Paul is known to imbue Koine Greek words with his own peculiar meaning.  I  still  struggle with the idea the scholars who translate the word  'authentein' in the English translations as 'authority'  are at odds with the scholars who don't contribute to Bible translation as to this word's meaning.  If scholarship was united it would be reflected in the translations. 

Isn't the word being  translated 'usurp' of more consequence?   It is the usurping in 1 Tim 2 that makes us imagine the woman is not to usurp the headship of man which Paul talks about in 1 Cor.  11:3.

Paul's reasoning doesn't acknowledge societal concerns.  He is reasoning a defense from the order of creation and the nature of sinful man and woman.  In a word: Paul reasons from the scripture.