See my response to agip on portfolio construction and your reference to the Blackrock chart. I would also add, I am accused of cherry picking data, well stocks are going to shine when the data is gathered at a market high.
I am not sure what you mean by a large consolidation pattern. My view is that Federal Reserve policies have led to bouts of speculation with booms and busts as a result. That can be the subject of future debates.
In regard to the overvaluation debate I would refer you to the Office of Financial Research report Quicksilver Markets. In the report the Shiller CAPE 10, Tobin's Q, and the Buffett Indicator are at two standard deviation above the norm. I agree that you cannot identify a market top. Nevertheless, when valuations are stretched your forward return is reduced. A stock is more than a tikker it is representative of a long term sream of income. It is not a lottery ticket to be bought and sold daily. You are welcome to try if you wish. If you pay to much for that stream of income your return is reduced. I would be happy to see you prove otherwise. It matters little if the market moves up another 10% only to fall 50%. You still have wipped out your all of your gain. Feel free to prove how I am wrong.