You were right to challenge my assertion. I definitely no longer think this. I tested it off the dummy and went out of my way to make sure I was watching only DoT numbers.
My problem is that my build hits so many times it can muffle the DoT numbers! The yellow numbers from my hits would cover the white numbers and I was missing them. However when I stop attacking and leave the DoTs to just do their thing they're never yellow.
Sorry!
It's all good, I just might be the person who made that system and know it pretty well. :)