Design complexity is rapidly becoming a limiting fac- tor in the design of modern, high-performance micro- processors. This paper introduces an optimization tech- nique to improve the efficiency of complex processors. Us- ing a new metric ( ?Utilization), the designer can identify infrequently-used functionality which contributes little to performance and then systematically "prune" it from the design. For cases in which architectural pruning may affect design correctness, previously proposed techniques can be applied to guarantee forward progress. To explore the benefits of architectural pruning, we study a candidate Optimistic-Checker Tandem architecture, which combines a complex Alpha EV6-like out-of-order Op- timistic core, with some of the underutilized functionality pruned from its design, with a non-pruned EV5-like in-order Checker core. Our results show that by removing 3% of infrequently used functionality from the optimistic core an increase in frequency of 25% can be realized. Taking into account the replay overhead triggered by the removed func- tionality, the Tandem system is still able to achieve a 12% overall speedup.