Someone commented on how some of the higher ranked teams have played against
teams that have worse records.  Doesn't it seem obvious that this will occur?
If a team is 10-0, it's opponents have at least 10 losses.  If a team is
5-5, it's opponents will have 5 more wins, and 5 less losses.  This is the
key problem with ratings systems that include strength of opponent teams:
if you lose, that rating increases, whereas if you win, it decreases.
Therefore, I propose the following change to ratings systems:  when calculating
a team's opponent's strength, do not include the opponent's game(s) played
against the team.  This will eliminate the penalty to a team's opponent's
record for beating the opponent.