There was a very interesting comment from the Indy Star's PhilB in his post-Monday Night Football live chat with readers:
Jennings definitely gave more cushion than Powers or Hayden. I guess we have to attribute that to the guy's coverage skills. The Dolphins receivers had little problem running him back at least 5 yards, then making that out cut. I know it's maddening to watch. It reinforces that Jennings is probably nothing more than a fill-in guy, a nickel back when needed if Jackson is ever moved out of that spot.
After re-reading several comments in the post-game thread, one consistent criticism of Jennings was that he gave too much cushion to the Miami Dolphins WRs, in particular Ted Ginn Jr. Chad Pennington seemed to pick on Jennings a bit, always throwing his way whenever he needed to convert on third down.
First of all, you need to understand the construct of our defense, which is that we try to get pressure with our front four. If you get pressure with your front four, then you can drop your linebackers and your corners and safeties into zones, then you can drive on the ball and you can make the kinds of plays necessary – usually a hit that will knock the ball out to prevent those kinds of plays. In our style of defense, which is designed to prevent the big play – which we did a good job of Monday Night, by the way – you’re going to give up some of those depending on the coverage you call.
This game was really no different – albeit with more talented players on the opposition side – than the Cleveland game last year. We won that one on a sack/fumble recovery by (defensive end) Robert Mathis in the fourth quarter. We played a cleaner game last year. We had too many penalties Monday Night, and we didn’t to a good job stopping the Wildcat, but the talent level on their offense was better than that of Cleveland. Essentially, it was the same style of game. Our theory was, ‘Let’s not give up big plays if we can avoid them.’
The issue with Jennings is two fold: One, he isn't that great of a coverage corner. He seems to give big cushions because he is coached not to get beat deep. Second, when he closes on the ball carrier, which is what he is told to do, then he is not doing enough to create turnovers or disrupt the receiver prior to or after the catch. With Jacob Lacey looking better at corner than Jennings, and with the eventual return of Jerraud Powers, Tim Jennings might fall further on the depth chart.