It's not just clear, it's Cristal Clear™.
Here's a review of all the relevant literature on the topic: https://docs.google.com/presentation/d/1PKHVtO6hgwBJS1vafLyv...
Here's a review of all the relevant literature on the topic: https://docs.google.com/presentation/d/1PKHVtO6hgwBJS1vafLyv...
Where a giant group is compared to an extremely tiny group and the differences between them are used to make sweeping generalizations about everyone. When this is the quality to expect, it's just good practice to be skeptical.
Edit: Even if this weren't the case, the enormous spread of estimates when it comes to revenue impact really says it all.