I ran the numbers for a quick thought experiment: what if the bottom 4 teams on
adam's table win 2 PPG the rest of the way? How well do Atlanta and NYC have to play to stay above that? I calculated for Atlanta, and this the result:
CHI 1.45
HOU 1.50
POR 1.73
RB 1.77
This means that if these teams earn 2.0 PPG the rest of the season, Atlanta exactly matches them with the PPG listed next to them. I figure ATL's GD is so high they win if they tie on points, and NYC has one more point than Atlanta so if it gets the same listed PPG it finishes one point ahead.
I think this shows Chicago and Houston are functionally out of this race. The odds of either of them suddenly winning 2.0 PPG for more than 20 games while both Atlanta and NYC drop to 1.50 or lower has to be infinitesimal. Portland and the Red Bulls still have a shot, though this shows how hard it will be. Of course, RB is currently at a slightly better than 2.0 pace right now, but it seems inevitable that it, NYC and ATL all will slip somewhat from this level.