On the surface that probably sounds contradictory, but if you look at Forge for example and he uses that as an example I think of how the share price has dropped so much of late, yet the companies fundamentals havent changed and there hasnt been any bad news.
Investing on bad news; I dont remember how it was said as such but when there is fear in the market, ie now there is fear.
You wouldnt invest on bad news about the particular company and David Jones is a good example there, they dropped 18% in 1 day and due to the bad news of their announcement the drop was perhaps justified.