Many people don't realize
that the most sophisticated bashers don't bash. They "are longs just like you". They gain the confidence of fellow message board readers. They bash the bashers and pass along optimistic news and opinions. Then... they gradually instill the seeds of doubt through rumor and innuendo. Mind you, they "are still long", but have "heard" some things that they wanted to pass along. They might even offer to share the info in a private email, all the while knowing that "their concerns" would leak out. The movie Stalag 17 comes to mind.
A lot of people think of someone like sky when they think basher, but they come in all shapes and sizes. Think about it. If anyone had a substantial position in a stock and heard something seriously negative about that company, would they blurt it out on a message board? Of course not. There are a number of reasons you wouldn't do this, least of which would be the risk of hurting your investment. A reasonable person would try to verify the info and, if proven true, would just quietly unwind their position and move on.