Another great advantage of the PT tender was ride stability, especially at the high speeds frequently reached by those magnificent Hudsons and Niagaras! The tender was regarded as the worst riding car in the whole train because of the variable load that it carried. The suspension on a PT tender is far superior to that of a traditional 6-axle tender, resulting in a much more stable ride. And on the NYC, the PT's came with an upgrade in water scooping capabilities. The maximum speed was increased from 60 to 80 mph over track pans when scooping with the PT tenders, and damage and stress to the tender tank was reduced with the improved overflow systems.
Also, a question for Hot Water: wasn't "PT" also used by the locomotive builders to refer to "Pedestal Tender"? Not at all trying to challenge your NYC claim, I have read the same thing in NYCHS materials.
