You can still buy dips without necessarily waiting, I believe DCA and dip buying can co-exist without stopping your regular buys. You can always share your DCA amount into 5 parts and maintain your consistency with 4 parts and continue saving the 1 party consistently until your desired dip surfaces and you lump sum on the dip with already accumulated funds for it and if the desired dip doesn't come by, you buy up with the saved funds or use it to increase your aggressiveness for a while.
You have a point here, I think some investors don't understand that DCA method is a strategy of buying Bitcoin in a flexible way since we can buy with this method at all time irrespective of the market status at anytime given time wether during the dip or upsurge this method allows us to break in easily with what we can afford consistently.
Why will anyone even wait in the first place, the risk involved in waiting outrightly for the dip to buy is very much, you can wait and the dip refuse to come when you targeted it, since you don't control the market you can't necessarily say that you know when the dip will come,, so you might be discouraged along the line.
The idea you outlined is good, if an investor insist to buy the dip, the investor can follow the approach you just mentioned, the main thing here is that such investor has started investing already with DCA so to make it very easy for himself to still buy during the dip as he wanted he can go by this method or still he can still decide to have other plans aside the amount he uses for DCA, save it up and my be buy higher in a reduced price during the dip as he has always wanted.