Granted, the original post does sound a little odd, but what motive would anyone have for posting such a thing if it wasn't true?
I guess a competitive hosting company could plant such threads in the hope that it would paint DreamHost in a bad way, but surely they realise that customers who had an entirely different experience would post and negate any such effect?
Personally, I can not fault the response speed of DreamHost support. Whenever I lodge a 'site down' type of support request (thankfully, not very often), I always get a prompt response. Also, my general enquiries, while not being answered quite as quickly as outage reports, are generally handled within 24 hours.
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