I am sorry... But I cannot understand why anyone will pay for three economy seats for two people instead of two Premium Plus seats. Even worse, two economy seats for just one person. Unless the savings in total cost is really substantial and significant. Consider that the PP seats offer:

-- Wider and more comfortable seats with more pitch.
-- Up to 3 inches more recline, which could put you in a comfortable position with the footrest or leg rest.
-- Larger entertainment screen with good quality headphones, same as those in Polaris
-- Better food, mostly similar to Polaris with some exceptions, and usually a very nice pre-arrival meal/breakfast
-- Free liquors (if you care for those)
-- A much more comfortable pillow and Saks Fifth Avenue blanket
-- Many other amenities such as an amenity kit that sometimes comes in handy if you happen to need a toothbrush or eye mask in the middle of a flight, premier access (if you do not have status), and several other little perks.