I think that document is assuming that you have a non-gmail address for both the primary and alternate addresses. In that case, you can "change" the non-gmail primary address to another non-gmail email address. But, you can only use your existing alternate address if you first remove it as an alternate.
When a Gmail address is the primary email address and you want to promote the non-gmail alternate address to primary, you have to remove Gmail from your Google account and the alternate email address will be promoted to primary. (Then, you probably want to go back and add a new alternate non-gmail address.)
So, the thing you have to decide is if you want to "cancel" your Gmail account so that you can use a non-gmail address as the primary address on the Google account.
Caution: Be sure (before removing Gmail) that you still have the non-gmail address listed as an alternate and that you can log into the account by using that email address. Otherwise, you will accidentally delete your entire Google account. |