You're right, though I had assumed he was pinging whatever server speedtest had selected, which may be erronous.
Really, my point was that congestion is often localized in a network. The fact that it isn't present in a path doesn't mean it's an ISP gaming speed tests - though perhaps they'd be more keen on peering directly and avoiding congested transit if it makes them look better, and I would absolutely believe that would happen.
I think the argument is that the speed tests are testing ideal/non real-world usage. That seems an awful lot like gaming the results. A more realistic, indicative speed test might hit several servers at points around the country, or even world. Most of my internet traffic is not hitting a server on the outskirts of town or in the next small city over.
Really, my point was that congestion is often localized in a network. The fact that it isn't present in a path doesn't mean it's an ISP gaming speed tests - though perhaps they'd be more keen on peering directly and avoiding congested transit if it makes them look better, and I would absolutely believe that would happen.