Edited out
I would agree that buying each and every time on a specific timer (one a week, half a month, or a month) is beneficial to a person, rather than just waiting for a dump to happen (because it may not) because of the facts you and many others here talked about.
Yeah, That's it! using the DCA strategy of buying doesn't eliminate buying of DIPs but instead it covers beyond... Either the market is in a Dip or not the DCA strategy doesn't focus on that so you can buy dips or buy outside dips using the intervals you mentioned which is a good way of investing.
Think of it like this buying of dips is like a bonus to your investment, if you have a disposable funds after considering your DCA and other necessary stuffs then buying dips with such funds can be a bonus for your investment.