I just tried that momentum theory on the bitcoin closing data someone posted in a sibling comment. I get 715 days of a trend continuing (down->down or up->up),

I just tried that momentum theory on the bitcoin closing data someone posted in a sibling comment. I get 715 days of a trend continuing (down->down or up->up), and 739 days of the "trend" reversing: down->up OR up->down. That pretty much points at a random walk. "Momentum", and any other patterns people see, are imagined.