The presentation is there to convince you to use their script. I think more OSS libraries and software should convey such an attitude; I'm way more inclined to use software when the authors tell me that it's awesome and why.
I'm the author of headjs. Have to say here that the release date of this tool was supposed to happen much later. yesterday I came back to github on my regular visit and noticed that it had 100 followers! It was OUT. I don't know how.
anyway. I now stopped all my other work and start focusing on headjs. the bugs will be fixed.
BTW: the loader part of the tool can be used as standalone. Here it is: