I am a Silver Level Powerseller, just short of gold for a few years now. Every month I pay approximately $400-600 in eBay and Paypal fees combined. The higher discounts could really come in handy. The only problem is that my shipping DSR is always 4.7. Sometimes it rises to 4.8 only to mysteriously drop just when it's time for eBay to apply those discounts.
In my experience, buyers think that they should pay for what shipping costs actually are or less, period. They do not take into account time, money, gasoline or the fact that eBay and especially Paypal take a percentage of what they've paid us (an increasing percentage, which is 1% higher for international transactions).
Although I would love to create a lovely message such as the one in this article, I think my message would be more about shipping and less about overall scores. The funniest thing is my Communication DSR is the lowest number (not out of 5, but just compared to the others) and I don't really know what else I can do about it. I answer questions within minutes (or hours if I'm not around) and send at least one message to let a buyer know that their item is on its way to them. Really, I hate it when I buy an item and am bombarded by email after email about my purchase because they use an automated internet program.