You've described one scenario, in which people with confidence in BTC and people without confidence begin with equal amounts of money. In such a scenario, over time the smarter ones would make money on the market, and their votes would thus become stronger. However, the implicit assumption that the participants' gains in this market outweigh any other capital they might possess... that's far from an ironclad assumption. Many of the people involved in BTC trading are getting much of their capital from elsewhere.
Although they might possess other capital, its very easy to 'play with the houses money' or 'risk your original investment again'. You've got to overcome a lot of inertia to deposit MORE money.
Then again, even if it was true, I think your endgames are dramatically overstating the impact of market fluctuations. If people were playing around with bitcoins back when they were worth a couple cents apiece, why would those people ever abandon the project? If bearish investors pull out, someone else was holding the BTC, so why does the "smart bull" scenario have a bonus on "people use their BTC for something"?
Because the bull keeps his Bitcoins (because he thinks the Bitcoins are the future) he's got to spend them on something, as thats where his profits are going to. When people earn money, they tend to spend it. If he earned bitcoins, chances are he plans to spend them.
Obviously there isn't a single-uber-bull and a single uber-bear that will decide the conflict. There are tons of 90% bears 10% bulls and tons of 90% bulls and 10% bears. Its very unlikely to be a hard-fast split like I have examined. But the same concept holds. If the people that are more bullish than bearish earn money, while the people that are more bearish than bullish lose money, then the future is bright. If the people that are more bearish than bullish make money, while the people that are more bullish than bearish lose money, then it doesn't look so good.
Since there doesn't seem to be any monumental influx of funds since the crash, and the flight of funds seems to have finished for the most part, I can see this model taking hold.
Obviously, the bigger the difference between funds coming in and funds going out the less accurate this model is. But in the long term, I expect this effect to matter more than many people seem to think.