You are right but I think that after the first two or three years buying with a regular strategy let's say DCA, an investor can also learn how to tweak to various buying strategies to enable him have broad know of the market and more experience of which buying strategy will be best for him at various accumulation stage.
For example, a new beginner can start with his DCA regularly weekly, and after two years that he have gained more confidence in bitcoin, he can start saving funds to buy at the dip or use part of his reserve funds to buy at the dip, mixing it with his regular ongoing DCA to give him a better advantage of buying more bitcoin to increase his portfolio fast. He can even front laid his bitcoin investment if the price is going higher. However, whatever method that you think will work for you is what you should use as long as you keep on increasing your bitcoin portfolio.
You are on point, but how about after a beginner has followed your suggestion for two years and then decides to sell at a very good price in order to buy the dip?. I think the beginner should be able to buy more this time around as their DCA must have accumulated a lot over those two years. What I mean is that this DCA approach is very good, especially for beginners, assuming it is done for two years. After the two years, the person can then sell at a very good price, combine all the saved up money with what they get from the sale, and then rebuy the dip. This strategy should work fine, but the only constraint might be the timing of when to sell high and when to buy the dip.
The only mistake an investor could think of making while building their investment portfolio is when they try to track or time the dip as you mentioned. All this is not so necessary as you mentioned because it doesn’t give a good profit in return as a 4-10 years or beyond could give an investor, secondly I don’t think a 2 years investment can give a good profit as you mentioned but depends on the kind of investor we’re talking about. The whole idea about DCA is good and an investor can accumulate using DCA throughout their journey like when Frankolala mentioned about using another strategy after 2 years I basically think strategy should not be the problem because people now think of using different kinds of strategy even when it’s not right for example selling everything to accumulate during the dip can be classified as a bad strategy but people still go ahead all in the name of using a different strategy, use the perfect strategy that can work perfectly fine during the long run. In summary what I’m trying to say is when it’s time for the dip you buy and hold you don’t have to wait or sell everything and wait for another dip, just imagine starting another journey all over again and I don’t like the idea of starting afresh.