Material optimization is needed to tackle highly relevant challenges of the 21 st century. Electrocatalysis is not exempt from this urgency. Mixed metal oxides are a promising material class to be studied as an earth-abundant alternative for OER catalysis in PEMWEs. Screening the vast composition space efficiently is key to accelerating material optimization, where a brute-force approach (e.g., grid search) might be highly resource-intensive when subjected to millions of test samples. The typical countermeasure in HT studies is to reduce the testing time per candidate, compromising the amount of information extractable during the measurement. OER stability, in particular, requires extended testing to accurately probe destabilization. Electrocatalytic performance is highly impacted by the choice of the electrochemical protocol due to the dynamic electrode|electrolyte interface. In other words, the chosen protocol will decide the final outcome of an optimization campaign and its translatability toward real applications.