if panda was run as they claimed why would there be only like 11.8% affected queries ?!?! and that was the main introductory update. The entire web should have been shuffled upside down but no
That's a good point, but the same result would also be explained if it was done by keyword, starting with the highest volume. They never said which searches those were, but judging by the carnage and also the intent, you would expect them to be the high-volume ones.
Anyway, it's clear just from the idea that you can predict what percentage of queries are affected that it's not being run over the entire web as part of the general algo, which as you say would affect all queries at least to some extent.