Messaging is cards not used for intended purpose.
Slightly more info from DoC a few days back.
Apparently Amex really means the language in their signup terms? My heart aches for these poor people who had their 82nd charge card closed after using offers that were not intended for them.
If we in our sole discretion determine that you have engaged in abuse, misuse, or gaming in connection with the welcome offer in any way or that you intend to do so (for example, if you applied for one or more cards to obtain a welcome offer(s) that we did not intend for you; if you cancel or downgrade your account within 12 months after acquiring it; or if you cancel or return purchases you made to meet the Threshold Amount), we may not credit the welcome offer to, we may freeze the welcome offer credited to, or we may take away the welcome offer from your account. We may also cancel this Card account and other Card accounts you may have with us.
Edit: LOL I didn't even notice that the article you linked to already had the verbiage; I copied it from Amex.
"American Express has a vague paragraph about abuse in its credit card application terms..."
Not sure how that's vague? I don't recall hearing about this happening to anyone who didn't game the system.
What I gleened from this is, for the average consumers simply carry on nothing to see here. Seems the people getting shut down are major abussers and likely deserve what they get.
"My heart aches for these poor people who had their 82nd charge card closed after using offers that were not intended for them."
Put so well in Lyrics, My Achy Breaky Heart