You're screwed because you won't possibly be able to follow a well composed, well tested library with an extremely shallow class hierarchy and short, clear meth

You're screwed because you won't possibly be able to follow a well composed, well tested library with an extremely shallow class hierarchy and short, clear method definitions without the aid of comments? I don't think you're giving yourself enough credit. A quick glance at the source shows that the size of the program is a result of implementing the many methods one expects from collection classes in Ruby, not because the code is especially byzantine. In fact, I haven't seen a single instance of class inheritance; the author seems to have chosen to solely use a few well defined modules instead.