AA has emailed me with details of a Summer discount for buying AAdvantage miles. The discount goes from 10% if you buy 5,000 up to 25% if you buy 40,000. The link is here.
Frankly, it is not the most exciting offer they have ever run, but if you needed to get a few AA miles to reach a certain award redemption then this is better than nothing. And if you look at it another way, getting a 25% discount on the price is the same as getting a 33% bonus!