[fspeech]

Your point 3, a la Graham-Dodd, is how Buffett started. But later he realized that did not scale when you own businesses forever instead of trading them. Buying a whole dollar for 50 cents is great if you can quickly sell it for 75. Not so much if you hold it forever and it does not grow. So basically acquiring Berkshire Hathaway the textile maker on the cheap was an investment mistake that he acknowledged in his annual letters.

Price movement is not relevant if your stated goal is to hold the business and earn an income from its operations. Technology eventually becomes obsolete or commoditized.