Heloc Strategy to pay home mortgage down

[Salvador Carlton]

I recently watched a video in which one of the strategies besides buying Real Estate Investment properties was to use your Heloc to pay down your home mortgage because of the simple interest versus amortization schedule.  For example you have a Heloc for 70K and you send 25K to your mortgage for principal only payment.  You would direct deposit your income into the Heloc and use it as a normal checking account to pay Heloc down, bills, etc. You could still use the remaining of the Heloc to buy investment properties and take a distribution of the rents (if you want of course tax implications might be applicable) to pay down the Heloc and repeat process over and over.  It was also mentioned using your 401K to pay down your home mortgage as another avenue.  I was wondering if someone has used such strategy and their thoughts on it?