How is it supposed to predetermine whether account is SUL or not?

It would probably do nothing if the account is not SULed.
The request is to provide a way for SUL accounts not to be globally logged.

*** Bug 24471 has been marked as a duplicate of this bug. ***

Fixed in r75041.

Reopening with a recommendation to revert -- this is a thing that's very rarely of general use, but it clogs up UI for everyone.

ayg wrote:

Agree with revert suggestion.

thor.malmjursson wrote:

Seconded, thirded and fourthed. +1 to brion for the suggestion.

or at least make sure this is checked by default for users, it does appear to
be for me but not others.

It could probably do with a better local message to indicate logging in to the
wmf projects globally.

Brion started a mailing list discussion about this here: http://thread.gmane.org/gmane.science.linguistics.wikipedia.technical/52265

or at least make sure this is checked by default for users, it does appear to
be for me but not others.

I made sure of that. That's the true parameter of r75041.
It is correctly shown in the html:
<input name="wpCentralLogin" type="checkbox" value="1" checked="checked" id="wpCentralLogin" tabindex="4" />

What kind of browser are they using??

It could probably do with a better local message to indicate logging in to the
wmf projects globally.

Feel free to fix it. Can WikimediaMessages extension override it?

What was the usecase/reason for this?

Any progress on reverting?

Bug 28369 suggests yet another preference for CentralAuth.

Ditto. Yesterday we (WMI) had a Wikipedia editing course with some NGO people we're working with and they found this extremely confusing (not very scientific argument, but still).
I think this should be reverted as soon as possible, even before another solution is implemented; it's easy for us to get accustomed to a thing like this, which however is now actively hindering normal users from editing.

mhershberger wrote:

Unassigning default assignments. http://article.gmane.org/gmane.science.linguistics.wikipedia.technical/54734

r75041 was reverted by Brion in r106839 and merged into the 1.18wmf1 branch by Reedy in r106840.

One reason a user might want to log in to only one site is account security. An unprivileged account on one site might be privileged elsewhere. This use-case probably doesn't justify the UI clutter, though.

Anyone who actually wants this is probably a super-duper power user. If people want this, how about we have it as a hidden option. If people go to something like http://en.wikipedia.org/wiki/special:userlogin people login globally like normally, no check box presented, but if people go to http://en.wikipedia.org/wiki/special:userlogin?noglobal then it doesn't log you in globally (or presents you with the checkbox) So we don't have any ui clutter, but people who actually want it can use it (but then it'd be very hard to discover)

Comments from someone that used this feature (before the revert): http://www.mediawiki.org/wiki/Thread:Project:Support_desk/Unified_Login_changed_in_past_week:_no_longer_possible_to_login_to_single_account%3F

More than a year since last comment, there's still no provided rationale justifying the need for this -> closing.