One problem I have with this is the upgrade for the person who is not on the same PNR as me can only be requested at the airport on the day of departure.
This means my travel companion cannot take advantage of the 7-day SE upgrade window, which is going to make his/her upgrade difficult to clear, as most, if not all, open R space would have been claimed by then.
I personally would rather have 4 nominees instead of 2 nominees + travel companion upgrades.
I don't travel with a lot of different people each year, yet I don't have enough credits to upgrade a lot of different people.