You have a very good point, in that the stock market's current phase ultimately affects the health of all its constituent companies (in both a symbiotic and par

You have a very good point, in that the stock market's current phase ultimately affects the health of all its constituent companies (in both a symbiotic and parasitic relationship). But like you said, I don't consider it helpful to pay attention on a day to day basis, and I find it to be a more useful indicator for macrotrends than microtrends. In other words, my understanding of the stock market will influence my opinions about the angel investing and startup market en masse, but it would not be anything more than one factor in my opinion about a single company I could invest in. While it's true that companies with strong fundamentals do fail in a downturn, companies with strong fundamentals can fail for any number of reasons. Just as I'm not all that concerned with my Vanguard funds going down for a while because they'll be back up in 10 years, I'm not too worried about a single company with strong fundamentals getting caught with its shorts down when the tide goes out. If it happens, it happens; in the absence of other poignant data, however, I find it much more important to focus on the company itself and pay attention to macrotrends more infrequently. Besides, a market downturn is an excellent time to hedge long bets with shorts :)