The commercial deployment of polymer electrolyte fuel cells (PEFCs) hinges on breakthroughs in design and integration of highly performing and durable catalyst layers with drastically reduced platinum loading. In this context, experimental studies have shown an unexpectedly large increase of voltage losses upon a marked reduction of the Pt content. In an effort to unravel this behavior, physical modeling of porous electrodes is employed to analyze a wide range of experimental literature data. Detailed evaluation of the data reveals correlated trends in essential fuel cell parameters. These findings are interpreted in view of the tipping water balance that affects the interplay of transport and reaction in catalyst layer and gas diffusion media. As will be demonstrated, the performed model-based analysis warrants the definition of a correlation exponent that should be used to assess the merit of different approaches to catalyst layer fabrication.