it does. u go n read carefully
u login to yr account thru itunes...click account
for me i saw 2 computers used.. so i click delete all or something and now it become 0. its deleting all computers from having access to yr apple account (my interpretation). so u do not need to have the physical one with u to delete it manually. just like i have erase my hd and i cannot possibly unauthorised it becoz the reinstall os ... my apple acc isnt login at all so how to even unauthorised... but yet, 2 computers are already linked to my acc.
i dont think need to be 3 authorised coz i unauthorised 1 (my current imac) and it shows 2 so from there i can still see the button.
from the link, click (in red below) to expand the information n see a screenshot
To deauthorize all computers associated with your Apple IDIf you need to authorize your new computer and are unable due to already having five authorized computers, you can deauthorize all computers by doing the following:
1.Click iTunes Store on the left side of iTunes.
2.If you're not signed in to the store, click the Account button, then enter your account name and password.
3.Click the Account button again (your Apple ID appears on the button), enter your password, and then click View Account.
4.In the Account Information window, click Deauthorize All.
Note: You may only use this feature once per year. The Deauthorize All button will not appear if you have fewer than two authorized computers. If you need assistance on using this feature, please contact iTunes Store support via email (
http://www.apple.com/support/itunes/store/).