where consistency matters anyhow.
Unfortunately true.
In addition to all the other annoying variables (air density, ATF temperature, octane) you have to add intercooler efficiency (what's the actual output temperature?), time to spool, does spark retard kill more power than too rich (for the same degree of anti-knock defense).
When you read that "on a turbo car the tune is worth 500 hp", that's what they're talking about.