The explanatory text was removed because two of us felt that the manner in which it was given to the user was quite annoying (pre-pasted into the message composition window such that every user with a signature would have to delete the lengthy text every time they replied until they took the time to update their signature).

It would have been nice if an alternate manner would have been provided to point users to an explanation, such as the patch author or applier describing it in a reply in the PMD thread that spawned the idea and adding a link to that reply in the patch (which could later be transposed into a sitedocclan node).

But I didn't write nor apply any of these patches and so was not much involved with the whole thing other than kibitzing from the sidelines.