Quantum state engineering of light is of great interest for quantum technologies, particularly for generating nonclassical states of light, and is often studied through conditioning approaches. Recently, we demonstrated that state engineering approaches can be applied in intense laser-atom interactions to obtain measurement statistics which resemble optical “cat” states by using intensity measurements and classical postselection of the measurement data. Postprocessing of a finite-size sampled data set allows one to select specific events, here the processes that are energy conserving, corresponding to measurement statistics of nonclassical states of light. However, to fully realize the potential of this method for quantum state engineering, it is crucial to thoroughly investigate the role of the involved measurements and the finite-size nature of the postselection scheme. We illustrate this by analyzing the postselection approach recently developed for high harmonic generation, which enables the generation of optical cat states bright enough to induce nonlinear phenomena. These findings provide significant guidance for quantum light engineering and the generation of intense optical cat states with potential applications in nonlinear optics and quantum science.