I’d coach the pair as a relationship, not designate one permanent holder.
When one pivot comes towards the centre-backs, the other should be asking what space has opened ahead. Can they stay on a different line, receive beyond the first presser or connect to the 10?
If both come short, the opposition midfield can step forward together and you have made their job easier.
A useful reference is: can the two pivots see each other and the next line at the same time? If they are standing level and facing the same direction, they are often offering the same solution.
I’d use a build-up game with a front four target. Change how the opposition press so sometimes one pivot needs to drop and sometimes both are better staying higher.
The key is not “one goes, one stays” as a fixed rule.
It is recognising when two players are solving the same problem unnecessarily.
