McKinsey Interview-Round 1 Test and Workshop

So after languishing as to whether I would be able to re-apply to McKinsey, I ended up re-submitting my application 2 weeks ago. I just got the decision from them yesterday and it turned out to be good news:

Hello-

Thank you for submitting an application for a position with McKinsey & Company. We would like to invite you to participate in McKinsey's Interview Workshop & Initial Assessment (IWIA) in Boston on October 21st, 22nd, 26th or 27th. If you are not within or near Boston at this time, please contact me so we may discuss whether there is an interview location closer to you.

Since you've taken the test earlier this year, you will not need to retake it, but you will still need to come and participate in the group breakouts. Please understand the outcome of the IWIAs, however, is based primarily on the test while the group facilitators also provide input on your performance. Therefore, we would draw on your test score from the previous time that you took it. You can still sign up for a full session in our scheduling system on-line, and you could come an hour and fifteen minutes after it officially begins then.

So it's nice that I wasn't rejected, but a little peculiar that I am not re-taking the test. Last time I took the test, I wasn't invited to move on...if the decision to move on to the next round is "based primarily on the test" then what does that mean exactly? Is my test score good enough that I don't need to worry about taking it again? Is the test exactly the same as the last time so they don't want me taking it again? Are they just having me come to the workshop because I "complained" and this was the easiest way to appease me? I'm having a lot of thoughts as to what this actually means, but I guess the answer is really just a few weeks away.

If I move on past this round then they were serious about having me come back. If i don't move on past this round then it is more likely that they never really cared about bringing me back or they would have had me retest.

I'll let you know how the actual workshop goes. I'm participating in it on the 21st in the morning session (8:30-12:30). I'm hoping they will let us know our status within a few days after the session, although the last session they offer is on the 27th so we may have to wait until after that.