Power cords - a BASIC question

There's an orthodoxy in the Forum that power cords are important. This is misleading for it implies that upgraded power cords are important for all systems. Power cords can make a sonic and musical difference in high resolution systems, however, unless your system is well optimized regarding the basics of sound reproduction, then power cords should be down towards the bottom of your upgrade plans. Simply put, there are more effective ways to improve a mid-level system than power cords. My problem is not whether power cords "work", but with their pricing. Cabling, whether power cord, speaker or interconnects at the high end are ridiculously priced. Just an opinion.

Systems with digital components are more sensitive to power cables than purely analog systems. Digital components are notorious RF producers and can easily pollute the rest of a system. The filtering in power cords is probably doing more grunge suppression on the ground from the digital component than on the incoming electric power.