Let's have a science primer, specifically about conducting experiments.

Rule #1: do not do conduct experiments with your mortgage. Do not do any experiments that affect the roof over your head.

Rule #2: do not assume a company will let you pay in creative ways, as in two payments instead of one, even if the sum total is reached by the due date. Mortgage companies are not design firms, they do not appreciate financial creativity. They take your "unauthorized" payment and put it in a special account that just floats in financial outer space and then gets applied to your principal. As if anyone around here cares about their principal balance!

Rule #3: if you conduct such an experiment and after a tearful plea, get the mortgage company to accept your two unauthorized half-payments for the low, low late fee of $85, do not tell your husband about it. Proceed to Rule #4.

Rule #4: blog abot it instead.

(Sorry sweety. I have a B.A. in English, i.e. blogging, not Math, i.e. bill paying).