The question to ask yourself is: After seeing the service clearly degrade, why wouldn't you stop? Also there may be a good reason why arXiv call it a DDoS atta

The question to ask yourself is: After seeing the service clearly degrade, why wouldn't you stop? Also there may be a good reason why arXiv call it a DDoS attack - they can probably see the same emails being flipped multiple times, which would not be inline with an accidental script issue.