I'd rather get what I mine than worry about variance.  I have never heard a reasonable reason for reducing variance.  The excuses I hear for the ramping up and down are always that it doesn't matter, which tells me that it does matter, or it wouldn't be done.  And second, that it reduces variance.  Well, so what?  I don't think that something that I don't want done (reducing variance) should be used to justify a practice of ramping up and down that I also don't want.