All the user needs to do is call it from the command line, and walk away.

As I read that line of yours there just came one thing to my mind. Why not to use peoples lazyness to their efforts? :-) Just put the call to your script in each users environment logon procedures, be it a Windows or Unix Box, that should work.

But hey, as I can imagine, the very first day a lot of angry people will (at least want to) meet you as the files they were working on (and wich they just by chance only the day before didn't finish to work on and hence didn't check in again, and we all know, that this only happens once in a lifetime, but nevertheless a genious work has been wiped out ...)

But knowledge of an automated procedure will result in following the rules to not to break the procedure or in circumvention of the procedure, and as we all know, every programmer feels sometimes like root, erm, I mean good and is of course creative enough, to easily break the whole thingy.

to summarize and to get back from humour to life's hard thruth: They fear that your tool could FORCE them to change the way they work in. As others said before: go and sell your product.

Have a nice day
All decision is left to your taste