I have found this topic very interesting. Thanks for the article Luigi.
My main reason for drafting either pairs or line-mates has always been to deny points to the opposition. It doesn't always work out perfectly, but with some well-established duos like Ovie and Backstrom, generally, if you own one but not the other, it allows the opposing GM to treat his player like an anchor to your team, making that team drag yours along with it. I find this really only works in pts-only leagues, since in multicat, there are so many other factors.. This strategy works even better in playoff pools, where the games played are limited, but those are an entirely different story. I generally like to collect pairs if I can and also, if they are productive on their own usually but are even better with their usual pair-mate.. (partner? lol).
I would love to delve into whether this actually makes a big difference or if it is my perception of the advantage. I feel it's self-evident, but being a guy who loves numbers, I would love to see some ratios applied to test the theory.. I wonder if there is any research out there...?