Unfortunately there is only so much that SE can do. Especially if the SE servers themselves aren't the ones being targeted, or even if they are only intermittently being targeted. The moment the attacks are focused on the ISP routes leading into the Datacenters there is absolutely nothing SE can do. Which seeing as this last month SE isn't the only ones to have been attacked, even Youtube was taken down by the DDOS attacks, there is nothing can be done until the culprits are found. It's only a matter of time before they hit someone they shouldn't and the pain is returned 100 fold.