Important point here is that if:

- you have lots of large files which are not amenable to diff and change frequently;

- everyone is working within the same company, and usually on the same network;

then a DVCS is unhelpful because you have to spend the disk cost for the repositories on every machine having a full copy of everything that's ever been checked in, regardless of whether they need it or not.

Many games are tens of gigabytes when shipped. It's easy to imagine a process which accumulated hundreds of megabytes of asset changes every single day over a multi-year development process. Then you can imagine having to have expensive terabyte SSDs just to work on it with all your tools.

I'm actually looking at this problem at work for possibly converting a large repository from svn which is a decade old and merely tens of gigabytes. Frankly svn handles it just fine so I'm going to defer the problem until I absolutely have to migrate.