I found myself scratching my head and groaning at several points in the article. "Liking" or "hating" a company should have very little to do with investment. I would exempt decisions based upon ethical or moral considerations.

My father did very well by researching a company's past performance, but he spread the risk around by acquiring equity in something like twenty-five or so companies. Two or three were duds, most did very well, and one was GE, which was spectacular. My approach was less sophisticated - I put money in index funds and that has worked just fine. The main thing is to not be greedy, and try not to make a killing overnight. If you are comfortable with a reasonable rate of return, investing can be as exciting as watching paint dry, but far more lucrative. All this is past tense for me. I got out of the market about five years ago.