Pushing a battery too far can affect its characteristics. What tradeoffs Tesla made in the protection circuitry (is it more important to protect the battery's lifespan or get you to your destination this time?) is interesting, but getting at it that way could well change the outcome of the current test if they've opted to stress the latter.
I have definitely done things to batteries, in devices with poor protection circuitry, that have lopped off a good portion of the time that the battery would hold a charge. Since the ultimate complaint was how short a time the battery held a charge, it doesn't seem irrelevant at all. If I'm complaining about a leaky bucket, the fact that I did something that may have added holes is highly relevant. Looking at the data Musk posted, it doesn't seem to have likely been the cause here, but that data wasn't available when the article was written.