DCA is a method with a lot of potential for everyone. It allows investment to be set at an average price so it can be used by everyone. It is more beneficial for beginners because those who are experts in trading or holding can make better decisions by doing various types of research and are able to make higher profits.
This strategy is good to use for everyone but it is more helpful for newbies. First, the strategy helps newbies to get rid of falling in love with trading or worse with leveraged or futures trading which risky and can cause massive losses. Moreover, this strategy helps newbies to gradually accumulate bitcoins with time and after several months, one or two years, they will surprisingly accumulate very considerable bitcoin for their portfolios.
But it is not possible for newbies to make accurate predictions because they don't have a deep understanding of the market and Bitcoin, so they will leave everything to their luck and invest. For this DCA has many impotent methods that can protect them from major losses. But everyone should follow DCA for fund safety
DCA strategy basically helps investors to avoid making predictions on next trend or next movements of the market. When applying this strategy, they can simply make buying on a basis they want and the basis needs to be matched with their income deposit and capital availability.
There is no such thing as DCA and smart DCA. You seem to be referring to combining DCA with buying the dip, which may or may not be a good idea, but it is another way of DCAing, since you can accumulate BTC by three buying methods, DCA, buying the dip and/or lump sum buying.
As I shared that strategy is for experienced investors, not for newbies. With newbies, they lack of experience in the market and if they apply smart DCA or as you explained, a combination of DCA and buy dips, they will struggle to make their decisions for purchasing dips or wait for deeper dips and at the end, they probably will miss many dips and waste many great opportunities to buy discount bitcoin.