In the article they mention Warren Buffett's trading strategy:
Warren Buffett, the most successful investor of modern times, has often said that he only invests in what he knows. His preferred holding period: forever. With that model, his company, Berkshire Hathaway, has averaged a 19 percent annual return since 1965 which means it has risen more than 1 million percent.
While this is true, Berkshire Hathaway is something that he has control over. His long-term investments are generally in established fields which are stable. He does invest long-term, but he certainly wouldn't invest in Bitcoin over the long-term.
I would say that the smartest way to deal with Bitcoin would be cost averaging - just buy a set amount on a regular basis and then sell or spend whenever you need money. That way you're separate from both the panic buyers/sellers
and the HODLers.