That's funny, when warmed up to operating temperature 10-30 and straight 30 should have the same viscosity, that's what the second number "30" means. The "10" would be a thinner viscosity when cold. Therefore, in my opinion, quicker elapsed times with 10-30 versus straight 30 don't jive with the science of oil viscosity at higher temperatures, unless the time trials were done with a cold motor.
