I remember he got flack for days when he said it. But I remember turning to my wife and saying he's getting good advice from Buffett (who was one of his econ advisors). I also pointed out that he focused on LONG-TERM (like Buffett). Anyone good at investing realized this. Even Fred Wilson talked about buying up Amazon (and a few others) when its p/e was insanely low...around this time.
We saw a similar trend in sensex when the UPA government was re-elected with a clear majority. government stability or its future guidance does reflect on the country's macro economics.
It all depends on how frequently he talked up the markets. In the unlikely event of this being the only data point, then the man is an investment genius.
I think it really was perhaps the only time he advise to buy stocks. It got a lot of news attention at the time since it was so unusual for a president to give stock market advice. But I'd be curious if people can find other statements that so directly advise to buy stocks.