Something I've always wondered: if all these tweaks give extra performance and should be benchmarked instead of the defaults, then why are those tweaks not the defaults? Default values are (normally) set for a good reason, and while I do think that tweaks, multiple hardware configurations, etc, are required for a comprehensive analysis of a particular item, benchmarking alone requires some baseline, and that will be your default system.
When various tweaks prove to be suitable and stable, I'm sure they'll turn into default values.