Short ribs come from where a riding saddle would set if you were to put a saddle on a cow or steer. It's a very tasty cut, but not necessarily tender and sometimes requires special treatment, such as butterflying the meat beside each of the ribs using an accordian cut - laying it out in a long ribbon, just as the Koreans do, and then BBQing for a long time, or one of the most popular methods, and my favorite, is braising.
Your ribs were still tough because you most likely haven't cooked it long enough. Tender meat comes from breaking down the colligen with heat applied for a long enough time to melt it. Short cooking times only serve to cause the colligen to draw up like a spring and tighten everything it's attached to. If it looks done on the outside but is still tough, it was probably cooked at too high a temperature for too short a time. Low and slow or paper thin and quick is the only way to go for certain cuts of meat. With ribs, low and slow no matter what method you use.
now i wonder what the difference between brisket-style short ribs are and real ones. i bet the brisket-style has a real name too.
