The 2300 was designed with FAI Pattern in mind, which means that the fuel draw could be compromised in some of the maneuvers. -- When fuel draw cannot be guaranteed to be constant, higher-oil fuel is used to prevent damage from the times when the engine is running leaner due to the different fuel draw rates.
This must be a true statement for any engine, how would the oil content for the G2300 change if you could guarantee fuel delivery by adding a fuel pump?