Now I do understand your point of view and method. Thanks!
I visit a hydro greenhouse in my area now and then.
They can measure single elements in their (huge) reservoir.
So they do top off with water like we do, but they add single elements to get to the perfect balance of elements every day.
The big problem that we face (in recirculating systems) is that after just 1 feed, there is already an imbalance. And the imbalance will get bigger and bigger by the day. Just because roots absorb different elements at different quantities.
By topping of with RO water your imbalance will not disappear. Also you risk that your EC will go down.
By topping of with a 33%, 50% or 100% solution the imbalance will also not disappear. And the risk that your EC will get to high.
If 'repairing' the imbalance is your main goal, then there is no proof what will work better. The only proof that one could get, if you could measure every single element or send your water to a laboratory every day.
Perhaps there is a grower here that has the financial means to do this