This is also grossly how I see it. Except that the arcs become wider and wider (longer and longer periods of down between the bubbles). And look, we're heading for the next few years towards something like $3000, and the next bubble is maybe 5 or 6 years away. The first one of size was in the summer of 2011. The second one was at the end of 2013 (so 2-3 years). The third one was at the end of 2017 (so 4 years). This is why I think we're in for a bear period of a few years, down to a few $1000. In 2014/2015, we went down a factor of 6. In 2012, we went down a factor of about 10. And then of course, there may be a last bubble. Hard to say. Once everyone has been burned once, where is the new army of greater fools ?
Definitely don't think it's gonna get longer and longer bear markets. That analysis only makes sense because of the Mt. Gox crash. You take out the hack of Mt. Gox and it all falls apart. That was a singular event in Bitcoin's history, not the trend of what has happened. Very unlikely Bitcoin isn't above $20k this year, I'd expect it to happen this summer. We're already about double from the bottom of the crash. When it doubles again it'll be at ATH. Sure it'll take a bunch of choppy months to get there but no way it takes years, unlikely to even take one year. Look at the crashed that didn't involve Mt. Gox to get an idea of Bitcoin's pattern instead of just focusing on that single event, it was an outlier. If Coinbase is ransacked and goes out of business then yea sure what you say might happen, but that again relies on one singularly important catastrophic event happening, not the overall trend of Bitcoin.
If anything I think bull markets will become longer and more gradual. The last boom phase was basically May - December, that's 7-8 months, and only in the last month and a half of that did it enter mania phase. I think we'll see longer "boom phases" in which the price is increasing steadily to ATH followed by quick mania phases like we just had the precede crashes. The thing is the only thing we lose from the crash was the mania phase, all the gains from the relatively gradual buildup from May through October remained even at the bottom of the market a month ago. That's real adoption that occurred, only the mania phase got erased temporarily. Real adoption will continue to occur and as adoption spreads these phases will last longer and the network becomes more diverse therefore stronger against crashes making long crashes even less likely.
This down period from the ATH might last 6+ months, but the next phase of real adoption might last until Spring or Summer of 2019, and it might just double the price over that time followed by a mania phase that maybe pushes the price into the high 5-digits that then gets wiped out in late 2019 and sends the price back to $30k or so. And on and on this cycle continues.
Anyway it's all a guessing game, but when you take out Mt. Gox the trend is that down markets last 6-12 months generally, and Bitcoin already being up about 100% from the bottom of the market and we're only 2 and a half months removed from the start of the crash I think very much supports the idea that it will push to new ATHs by this summer.