Your record is your record, it does not dictate how good you are.
Actually it does.
Otherwise what is the point of even playing the games?
Why not let an expert like yourself just judge the two teams on paper and determine a winner that way?*
If it did the team with the most wins would win the WS every year.
Actually that is the way it works.
The team with the most wins in the playoffs wins the WS every year.*
Teams can have more or less talent than the record would indicate.
Wrong.
People can perceive a team having more or less talent than the record would indicate. Doesn't make it true.*
The point still stands. With a league average closer they would have been over 500.
The point is still wrong.
A league average closer makes a 1-2 game difference at the MOST.
Marmol has 3 blown saves, the Cubs ended up winning one of those games.
Kevin Gregg has one blown save. The Cubs won that game.
So a league average closer isn't a perfect closer and may not make the difference in any of the above games as league average closers still blow saves.
I am not sure even Mariano Rivera makes the Cubs a .500 team*
* = 100% baseball related content