Per the tale...
Some coders (myself included) have a sort of customized shorthand that they use to make inline comments which are thoroughly explained in outside documentation (notebooks, sketch pads, websites, wikis, whatever). One person may code something one way, and another person code that same thing another way. Both sets of code will work, but only one set will be pushed for publishing. The mixing up of code/comments/documentation is what kills a whole lot of collaborative projects.
That said...
While moving from Texas, someone (an intern? janitor? mover?) tossed a box that included handwritten notes and documentation on portions of the UO source code. Some people suspect it included notes on the housing code, which could explain why changes to housing are fraught with disaster sometimes.
While the source code itself was on servers (a depository I believe, or we wouldn't even have a game to play) - the documentation and notes contained information needed to help keep the code organized. RG et al were breaking new ground with their development, and those notes were crucial in future planning. I'm sure a lot of things were managed due to the prolific picking of brains - but not everything can be done by memory. Inline commenting, although an industry best practice, is not always feasible (makes for bloated software and long compiling times - depending on the number & size of comments).
I'm sure after this fiasco, the involved parties have developed mass redundancy for their documentation in all its forms.