Agreed. It's too bad there aren't effective mechanisms to go short though, so people who think we're at a peak can back their view with money.

What are you talking about? Also every exchange out there will let you short any number of cryptocurrencies.

I do not personally believe the bitcoin markets will function properly for the shorting mechanism to pay off in interesting scenarios.

If I borrow your bitcoins, how will you force me to sell them? If we agree that a third party will warehouse those coins, how can I trust them? And if BTC plunges, who's to say that 3rd party will still operate?

All very different from shorting a stock.

But if you want to loan me your bitcoins, let's talk!

I'm also interested in borrowing any other bearer instrument that you possess? (Now thinking of bearer bonds in the movie Heat)

People successfully short cryptocurrencies every day and reputable exchanges pay out, even during massive drops. If you really want to short, sign up at GDAX and enable margin trading.

"It has worked ok so far. Therefore there's no problem."

You want to suggest that they would not pay out if Bitcoin crashes to zero? Maybe. They are not regulated after all. They might also be bankrupt before Bitcoin hits zero.

Still, you can short these 30% drops without problem.

Did shorting the housing market work out well in the crash? I remember a movie with Christian Bale, where it did.

Yes, some people successfully shorted the housing market. But they did not use bearer instruments to take their positions.

https://en.m.wikipedia.org/wiki/Bearer_instrument

Also, counter party risk was a major issue during that financial crisis.