Yep. This is what happens in the NFL a lot. You look pretty good on paper, the by week five you are missing 1/3rd of your starters and a few more are playing hobbled.
Disappointment is becoming a fall tradition in Chicago unfortunately true. the annual derrick rose injury will be the final blow I dunno. I wouldn't mind waiting until the spring to get a "competitive 4-2 loss to LeBron in the playoffs."