Doesn't work like that, purely based on team performance, together..
Doesn't it work literally like the word sounds: Eric's doubles ranking + Jamie's doubles ranking, then it's compared to the rest of the field? If it's purely based on team performance then how did Aspelin/Knowle get seeded seventh in Monte Carlo given that they only have a 3-2 record together?
Source: The ATPtennis Rulebook
, page 76.
I believe only the Race rankings are team-specific, but qualifying for a tournament main draw is based on the players' combined rankings.