We're not sure if we're going to keep this, so it's not fully fleshed out; it's more of an outline of what we're thinking it will look like. For now we'd like you to give it a try and let us know if this is something you find helpful. We figured for learning about specific parts of the site, it would be easier to have informative text on the page itself, rather than nested deep in a user's guide where it's detached from the material it's referring to. If you guys like it, we'll expand on the text and put overlays throughout the site. If you don't... well we'll think of something else to try!
Assuming the overlay is kept or something similar is made, the userguide will be trimmed down and reoriented to providing overviews, rather than specific details which the overlays will handle. Things like how managing your vocab works or how to get the most out of practicing or how Skritter can be used effectively as a teaching tool.
This is just one more experiment to try and make Skritter easier to use. Let us know if it helps!