Didn't Cotterill say early on that we would concede goals, but aim to score even more, or something like this?
You say we draw too many - that's simply because we're drawing rather than losing. We have the best points per game ratio in the entire football league, and even if we include the Premiership then only Chelsea have a better ratio.
I'm going out on limb here, but I would hazard a guess that Cotterill has noticed the ball going into our net. He might even be thinking how to stop it happening so often.
Finally - why speculate about the risk that Cotterill will display the same faults (retaining players too long) that previous managers have? He's shown himself happy to leave players like JET and El Bad out. You might as well say that previous City managers have walked out on us, and we need to take action now to stop Cotterill doing the same.