It was inspired by Wakui's work, and attempts to produce a similar glow/bloom to highlights in an image, which it sort of achieves. The overall color grading could be pushed further, but the author wasn't looking to exactly match the style.
As a single _example_ of one (of many) possible interfaces for it? Seems to hardly qualify as 'billing' as much as one example of how it might be used...
It should be noted that the project CIMG/GMIC is _not_ built and billed as an IM alternative. It's an image processing framework that happens to have similar utility to IM for some folks and that is also available as a plug-in to GIMP for visual+interactive use.