I've always gotten great support. It's natural that responsiveness will vary but not the actual quality of the answers. It's probably also natural that the level of niceness will vary as will the level of communication as to how things are progressing in addressing your support issue. These last two things can be made much more consistent through a good training program, so if you think these are areas where dreamhost could improve, I suggest that you speak up.
For example, my cable company has gone on a massive "niceness" campaign where they still have the same terrible service, but their agents are always very apologetic and nice to you when you do communicate with them.
But I suspect two important aspects affect the responsiveness of support - how busy they are at the time you report the issue as well as how well you communicate the particulars of your problem. If they're experiencing sytemwide problems, responsiveness will decline because their resources are stretched thin and it's often very hard to distinguish issues that are tied up in the systemwide problems rather than specific to your account. Secondly, you can get much better support if you do a good job of describing your situation, the symptoms, and what you think could be the cause of your problem. This all just makes it easier for your happy support person to figure out what's going on much more easily and much more quickly! Someone here once posted a link to a funny post about this effect.
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