>Despite this, I can't say for sure that they'd sell given some serious volatility. There's a growing cult like groupthink attitude best represented by the phrase "HODL".

True, but the rise in price seems to have largely been due to newcomers entering the market who don't share the attitude of longtime HODLers. See: Coinbase shooting to #1 on the App Store. I think that raises the odds of a crash considerably. The new crowd is in it because they expect the rally to continue and if they realize it won't, they'll want out en masse ASAP.