You might pull out now to take profit and expecting correction to occur for one to buy back, but it might go the other way of bull as you said, and except one is just lucky enough to just make decision based on believe that wherever point one is buying back from, it will still go further from there.
Yea, you're right that you have to time the market to get in and out in some way, but the purpose of the post is to describe a strategy that encourages reasonable profit defense without having to worry so much about making the best timed trades. With a deep understanding of how markets work, it is possible to get better at that on your own. However, that's going to be an uphill battle against all the misinformation out there.
I choose to accelerate my path by learning with Voodoo Crypto. They taught me more as a trader than I could ever hope to share, but I'm doing my best to do just that.
edit: broke the quote, fixed now