Usage of .local for AD predated mDNS. That advice stopped with the advent of mDNS in favor of 'corp.<registered_domain>.<tld>'.
The original Windows 2000 guidance for AD was corp.example.com, from my recollection. The silly .local thing (which does predate mDNS) happened as a result of the Small Business Server refresh for Active Directory.
The original Windows 2000 guidance for AD was corp.example.com, from my recollection. The silly .local thing (which does predate mDNS) happened as a result of the Small Business Server refresh for Active Directory.