Short answer: His rank isn't impressive, but I think he'll continue improve.
Longer answer:
Like GV noted, his Offensive Rating (ORtg) was 95.x (depending on your source it can vary just a tiny bit, but it's all about the same) which was negatively affected by the things we've talked about in this thread. However, he does a lot of things well and is capable of producing a very good ORtg in the future (and I think he will, whether it's at CMU or elsewhere).
The ORtg measures personal offensive efficiency. While it's a precise measurement, taking two players and simply comparing their ORtg doesn't necessarily tell you much.
Going a little bit deeper (see www.crackedsidewalks.com for an explanation of Offensive Value Add), Zeigler did add a little bit of offensive value although not much. This measurement is far more complex than a personal efficiency calculation, but I think far more telling. A key thing to remember (and it's important when looking at a team like Minnesota and its players) is that players who both (a) are more involved in the offense and (b) play more can generate more value to the team.
Zeigler played almost 4 of every 5 minutes and was used in 31.6% of his team's possession. That is significant.
Not to get into this too much here, but when I look at the potential of teams in the future, one thing I try to do is look at which players I think are capable of adding significant value. ORtg is certainly important, but you also must consider how involved in the offense the player will be and how much they'll play. (and if a guy is going to be called on to do more, what will that do to his ORtg?.. diminishing returns, forcing, etc.)
Interesting stuff there. Frankly, a tad too deep for my shallow mind, but I appreciate how you can dig in with it. Off topic with this specific subject, but how much do you think coaching staffs across the country pay attention to some of these formulas when making playing time decisions, grading out players, etc? Seems to me some really smart coaches could benefit from some of these number-crunching things (like a hoops version of Billy Bean). I am guessing Tubby's staff doesn't use some of these components as I've never heard him discuss it. Any idea how much Tubby uses any of this kind of stuff, or how much staffs across the country try to benefit from them? Like I said, too much for me to dig into, but I think an aggressive staff could potentially benefit from these readings. Thoughts?