A comparative analysis was performed between self-consistent field theory (SCFT) predictions for the force between semidilute polymeric brushes and the benchmark experiments of Taunton and colleagues. Researchers also attempted to differentiate between strong-stretching theory (SST) and self-consistent field theory (SCFT). The method of Cooke and Shi10 was employed to investigate the effect of polydispersity in case the SCFT is expanded in moments of the molecular weight distribution. The SST and SCFT, all two are based on the exact same underlying model and mean-field approximation. SCFT offers a significant quantitative improvement over SST, yielding excellent agreement with the experiment. The observed effect of polydispersity was relatively small, whereas the effect of chain fluctuations was so large that it cannot be ignored.