> I respectfully disagree with the second half of your response. On a 6 system the distributing valve will see leakage as a reduction, and will apply the independent proportionately

If by "leakage" you mean "brake pipe leakage", this is not what is happening. What you are describing is the automatic part of the the distributing valve functioning to apply the locomotive brakes in response to the decrease in brake pipe pressure.

Both the distributing valve and the independent brake valve operate the locomotive brakes. The reason "the independent" is called "independent" is because it operates the locomotive brakes independently of what the distributing valve is doing with them in response to brake pipe pressure. This principle of separation of functions is precisely the same with the 5, 6, 7, 8, 10, 12, 14, 22, 24, and 26 systems. WABCo identifies its locomotive brake systems according to the designation of the control valve, which means that a "30CDW system" is still the #26 system because it uses a 26-F control valve.

It is in the nature of the design of all these systems to maintain against brake cylinder leakage, whether the brakes have been applied by the independent or the automatic.