Why changing the negotiators changes the treaty

Would you replace any of the historical negotiators with different members of their governments when designing an equitable treaty?

Changing the representatives would create a substantially different counterfactual; the equitable version is mainly a benchmark for explaining where the historical treaty departed from an acceptable compromise.

An equitable benchmark helps a historian explain where a settlement falls short of an acceptable compromise. In this usage, a fair arrangement treats everyone the same, while an equitable settlement accommodates different expectations well enough for each participant to accept it. Nobody receives everything desired. Replacing the historical negotiators changes the assumptions of the exercise and moves it toward a different alternate history. A foreign service can prepare for negotiations by estimating an equitable outcome and the other parties' minimum needs. That preparation identifies possible concessions, while the bargaining principle presented here is to seek reciprocal movement or political credit for what is conceded.