You can always find example that fits your bias. One way is to take the Nasdaq and say that the run up to 2000 was a bubble (and I tend to agree that it will not recover to new highs in the next 4-7 years)
Indeed. It's always possible to find data to back your bias. I present, the Japanese stock market.http://au.finance.yahoo.com/q/ta?s=%5EN225&t=my
That's one hell of a bubble, still very much burst after 20 years.
Gold's 1980 peak still hasn't been equaled, when adjusted for inflation. Gold may eventually go higher than ~$2700 (official US inflation figures) or ~$10,000+ (using more extreme 'real' inflation figures), but if a 40 year old trader in 1980 needs to wait 35+ years for that to happen they'll be retired or dead by then. The bubble may reinflate, but it doesn't do those that saw the original burst any good.