Mr Market, You say you would prefer to hold stocks forever. So would I! We both know that this is not a good idea though. The bluest blue-chip does not keep going up for ever. I have a lot of sympathy and understanding for your approach. In fact, I used a very similar system for over 10 years when I first started out. I was happy enough with the "buy" side, but gradually became increasingly dissatisfied with the fact that I was giving a lot of my profits back to the market by holding stocks too long. The crash of '87 was the last straw. I lost an awful lot of money and it took me over 2 years to recover. The lesson that I had to be a lot more active in order to protect my capital and profits was rammed home. Never, ever again, would I pursue a "buy and hold" type of system.
Look at the charts of RBD, BGR, CAV, HBY, TLS, SCT, TEL etc etc etc. Every single one of these stocks was in a really good uptrend for literally years. Each and every uptrend ended. I have held all of these stocks, selling each one when it became clear that the uptrend was over. Anyone that continued to hold such stocks ended up giving the lion's share of their profits back to the market. I won't mention Snoopy because Duncan thinks I am picking on him.
It's almost as though truly staunch Buffett followers have determined to emulate his mistakes too - take a look at this Coke chart. I haven't bothered to apply any technical indicators such as moving averages or trendlines etc because blind Freddy could see when the uptrend suddenly ran out of steam. Maybe Buffett has such a large holding of KO that he is stuck with it but he has certainly given a lot of his profits back to the market and would have been better off selling years ago. Sound vaguely familiar?