The thing is, if Google were to say “x was shared by y on twitter”, that is precisely providing some additional weight to the result. Human weight, admittedly,

The thing is, if Google were to say “x was shared by y on twitter”, that is precisely providing some additional weight to the result. Human weight, admittedly, though I believe this also factors into the weight on the page. So it makes sense that twitter links would also not be included in this sharing stuff either.