It appears that since r45973, there is an enhancement to MediaWiki that allows the software to follow double redirects, and conceivably triple- and higher-level redirects, up to a configurable limit ($wgMaxRedirects). This raises a few questions:
1) Should [[Special:DoubleRedirects]] be changed to show only those redirect chains that exceed $wgMaxRedirects in length, since those are the only ones that really need fixing under the current software?
2) If not, should there be a new Special: page to list such "excessive" redirect chains?
3) How can the users (not sysadmins) of a given wiki determine what the value of $wgMaxRedirects is for their wiki? In particular, what value is being used currently on enwiki and other WMF projects?
4) Shouldn't this configuration change have been announced to the user community of each project so that they could consider how it affects their internal policies on what types of redirects to allow?
Russ