Most mortgages are not set up for biweekly payments, meaning interest is calculated on the last day of the month, so anything you pay mid-month does not affect the mid-month balance.

If you want to make biweekly payments and have it matter, you have to have your mortgage set up that way from the beginning. That would probably be the only argument. Most people don't know to ask for that type of amortization before they close on their loan.

I pay my student loans biweekly because they accumulate interest daily, so it makes a huge difference. With my mortgage I simply make an extra principal payment towards the end of the month so that when they calculate my interest on the last day of the month, my principal balance is lower and therefore I pay less interest.