I think it would be helpful to add an optional "reason" field when creating an account for a third person using Special:Createaccount so that others can know the reason in Special:Log/newusers. It can be shown like:
00:00 1 jan 2009 User (talk | contribs | block) created new account for User:XXX (talk | contribs | block) (a reason here)
Thanks.
Version: unspecified
Severity: enhancement