The self-adaptive, multi-recombinative (µ/µ_I , λ)-ES (Evolution Strategy) is investigated on the highly-multimodal Rastrigin test function by theoretical and experimental means. To this end, the self-adaptation response function is derived in the limit of large populations, which are necessary to achieve high success rates. The established dynamical systems approach is introduced and steady state conditions on Rastrigin are discussed and compared to the sphere function. Then, a characteristic τ is derived to tune the sampling process of the self-adaptive ES. The obtained result is compared to default τ-values. Furthermore, expected runtime experiments are conducted varying τ and population parameters of the ES. Theoretical and experimental results regarding τ are compared in terms of efficiency and robustness showing good agreement.