The shortest delay on the "Snap to Default value" slider is 10ms, but that's too slow for a traditional (spring-loaded) Pitch Bend controller.
Previous requests have suggested adding options for 3ms and 6ms[0][1], and at one point this seemed likely to go into 1.7[2].
Those options seem reasonable to me. Alternatively, it would be fantastic if you could fine-tune values below 10ms by slow-scrubbing the slider.