Will former mining cards have reduced gaming performance?
they pitted a card that's been mining for over a year against a brand new one and found the one used for mining to be about 10% slower. the drop is chalked up to the wear / tear mining causes.
so there is that...but what they really need to show is how a GPU used just for gaming for the same time period would perform against a new one. without that information they can't definitively confirm mining does long term damage.