I think this works as long as you have income to pay off the debt and actually are paying off the debt. But isn't it a problem when:

- you're only paying the interest and rolling over the debt; that only works with declining interest rates

- your income goes down for whatever reason and you can no longer make the debt payments

- you think "I'll just sell the stock" I accumulated, but that may not be possible if the stock price is declining.

If your income goes down, your stock price is probably also declining at the same time, but you still have those debt payments to make.