I strongly suggest that you actually read Benjamin Graham's book 'Intelligent Investor' before you start following advise from the link you posted. While the article does identify one thing Graham lists as important in investment decisions (lower market cap than net assets), it falls far, far, far short of Graham's advice given in 'Intelligent Invester'.
It completely ignores the most important aspect of estimating future earnings and discounting them to present values. This is not a simple process, and Graham himself wrote that it should only be perfromed by qualified 'agressive investors'.
I think that article can be summed up as follows: "To every complex problem, there is always a short, simple, but completely wrong solution."