I would have just gone around with a clipboard.
Well, there are a few reasons I didn't want to go around with the clipboard. Some of the users aren't here (vacation, etc.), some work odd hours and it's hard to nail them down, others are remote dial-ins, etc. Cat herding, like I said.
I really didn't want to do all that leg work, I didn't want to make the users uneasy about giving out a password that I previously kept deliberately secret from even myself. I just wanted to have it magically work for them without troubling them about it. I pride myself on making sure my users are inconvenienced as little as possible.
And yeah, I also really wanted to see, technically, what it took to brute force my network's accounts. It's something I'd never done before and I wanted to know just how secure it really was. In the process, I've learned some pretty interesting things about NT/Lanmanager authentication and passwords. And I've got some nifty new tools in my toolkit now. So it's been worth it.