Same logic as in bug 42892.
Quoting Siebrand from the URL: «What is harder, is getting the actual work done. We need volunteer developers for that. If you know any that care about this area in particular, please point them my/our way, and I'll make sure that person will be trained so he's up for the job. Intermediate PHP skills and some familiarity with MediaWiki code would be nice».
[[mw:Manual:Logging to Special:Log]] contains only a bare example; Niklas seems to think this enough, but apparently it isn't for normal devs. The log rewrite hero Siebrand hoped to train has not popped up in the last year and hence can't be trained, so we need some distributed effort or anyway something concrete to point people at, other than "would you please rewrite the log for X?" "OMG scary I've no idea what it means no thanks".
Rancher, are you still interested in the topic and how would you like to help? Just crash-testing a draft tutorial/manual by working on the rewrite of a single log, to ensure the docs can successfully guide someone through the job, would be useful: am I correct, Siebrand?