The psychological|mental|logistical externalities that come with taking on debt usually render this strategy invalid.
If substantial inflation is on the way, the interest rate earned by your savings will increase accordingly provided you're not investing in mattress funds.
Well, the strategy would be to take on as much debt as possible with a low interest rate, then put it in savings accounts as interest rates rise (so the interest from the savings account will be > interest on the debt).
Saving can include investments. Real-estate is a good one.
Real estate is a horrible investment. Houses appreciate at a much, much lower rate than index funds.
Horrible? The recent bubble aside, I understand real estate has historically been quite stable. Any good portfolio is diversified, so I don't really see why they are horrible.
P.S. Many people who "invest" in real estate rent the property, which throws a tremendous wrench in comparisons of simple appreciation.
Rate of a return is way too crude a measure. Real Estate is more stable, tax advantaged and most crucially to your wealth creation, the only investment class where John Q. Public can get 4:1 leverage (or better!).
I know individuals that have made millions, including family.