DH uses it all the time and it drives me potty. I am a language teacher so tend to try and use simple language as much as possible especially when speaking to non native speakers.
He once answered the phone to DS' (German) kindergarten by saying "Ah, no, unfortunately Bertie isn't here, however I am in fact DS' legal guardian, if I can be of any assistance?" then was totally bemused when they said "Uh... is Bertie there??" Told him later he should have just said "No, but I am his father" and they would have been fine
he ended up texting me to ask me to call them.
He also uses in fact randomly, as referenced in this conversation.