And? Why do you think that matters to what I'm commenting on? Them moving to and from DC is almost certainly completely unrelated to any changes in WaPo's quality.
That there is a personal reason for why their two datapoints are before and after acquisition doesn't change that their two datapoints are before and after acquisition such that it's hard to use those two datapoints to exclude that the ownership had major effects on the quality of the paper's reporting, if anything, it seems extremely suggestive that it did.
