You must be kidding ..
I've been an ICT manager/systems admin for over the last 30 years and choosing the "wrong" system language is an absolute PITA which causes you the most unexpected quirks with distributed updates. No language pack is ever going to change that
So you were already an ICT manager/systems admin before 1979??
Even before anybody ever heard of ICT managers or system admins.
When you try to profile yourself as being something you're not, at least make it believable.
Language packs only pose a threat in the hands of numb-nuts.
I am not going to brag about how much experience I have to silence another person.
But I do live in a multi-lingual country and language packs never presented any problem what so ever, neither for me nor my clients.
And I too have yet to see any problem specifically linked to languagepacks.
So please present us with at least one valid example.
Greetings
You must make a fundamental difference between system install language and language pack ...
So for the sake of simplicity ..
You run a computer node of say 200 networked PC's, partially populated with company proprietary machines and partially with user owned machines. All seemingly run in the english language ... but you're already fooled at this level because several user's machines were not installed with English as the system language (quite logical in an international community of users) they only seems so because of the holy "language pack" syndome
(hey they used to call that MUI in the past, and one had to pay big bucks to MS to get it)
As a good manager you want to keep every machine up to date with the latest MS updates. Tough luck if you use an internal distributed systems update server. If you use the english version downloaded update all machines with a different system install language will fail with the stupid error "Your update is incompatible with the system language blah blah ..." and no language pack will get you off the hook .. So are you going to suggest to any user that they wack their PC installation an redo/install everything from scratch in the appropriate language so you can apply a uniform update policy in your node? I think NOT! ... and I've not had it only once ...
Oh & BTW .. for some MS applications you may need to wait until they see fit to release a language pack if it is not plain US-EN .. It sure serves your customer right ! ... and god forbid Mr that some of your machines have been installed in say "swahili" as a system language
So you may glue any language tail to your installed system to use it, when it comes to add other fundamental body parts you have to stick to the genetically correct match(language).
Try to Install IE8 english (because you want to upgrade as soon as it hits the public) release onto an English "language pack"-ed, Dutch cored version and see how far you get ... the answer is nowhere beyond the "not in the system language" error ...
.. and FYI I was a sys admin and manager and computer programmer and a lot more (amongst other things) from 1972 on, or do you think there was no computer life before the release of the IBM PC in 1980? and don't lose yourself in syntactical semantics stumbling over names! holy cow man! I used the fist versions of Windows and Word, yes version 1.0, in a production environment and GEM amongst others under DOS before that! I've seen lots of cr@p told before as well! djeezes, get a reality check will you? or do you think life started with Vista? (god forbid!)