From what I understand with the VB strategy is that by paying down more PRINCIPAL, you reduce the INTEREST for the rest of the mortgage. As an incentive for the banks to lend money for 30 years, they are allowed to amortize mortgages so that you pay more INTEREST (for example 90 percent of payment) and less PRINCIPAL (for example 10 percent of payment) at the beginning of the mortgage. So, by reducing your PRINCIPAL via a HELOC or your own funds, you will substantially reduce the overall interest you pay across the mortgage. Your agreed payment amount will never be reduced unless the bank re-amortizes your loan which is rare. Due to this, your mortgage length (TIME) will be reduced. That's what I understand from the strategies. And yes, I would run on calculators to see if it is beneficial for you. For example, if you are at a point in your mortgage where you are already paying significantly more in PRINCIPAL (towards the end), then it may be less beneficial. However, as an investor, I would utilize the equity in a property to purchase more investments.
