Thank you, this is very helpful.It's a 'good friends' network with Macfarlanes, 'best friends' is Slaughter and May. They can choose any firm they want - this is the advantage over having an office there. Plus it's an acknowledgement, I think, of the other firms' expertise e.g. Slaughter and May has worked with Paul, Weiss. Source: I tried saying 'best friends' network to a Macfarlanes Partner.
LOL about the partner story.