Unless you're a professional, odds are your equation has some errors in it.
Brewing coffee beans is like cooking garlic. If you use bigger chunks of garlic, the taste is mild; if you put garlic through a press or finely dice it, the taste can be overwhelmingly powerful, even bitter. This is why chefs harp about cutting into uniform size. Coffee's no different.
Dark roast is terrible in more ways than one. Sorry folks. Your oily, burnt French and Italian roasts are the antithesis of what today's coffee should be. It's not your fault that you've been told to enjoy this stuff for so long.
Recently, I had the chance to indulge my coffee obsession further with a visit to Cuvee Coffee, a Texas coffee roasting company that supplies beans to some of the best coffee houses in Austin.