Let me put this another way. You are asked to operate an A320 over it's max authorized Take Off Mass just to get a few passengers out or to avoid a fuel stop on the way home, do you take it?
Bearing in mind that we are talking about a training flight here what sort of example do you want to set for your new students who, one day may be faced with the decision in my opening paragraph.
To answer your question, NO I WOULD NOT TAKE THE LESSON.