running too cool, especially during break-in, is NOT good for your engine. These engines are in designed to run in the mid-200s (Fahrenheit), and tolerances are designed for that. You will have increased pinch, and thus increased load on your wristpin, conrod, and crank pin. When these start changing, your port timing also changes. This will drastically hamper the performance of your engine.
Also, although you'll have more lubrication, liquids dont compress. That means than you'll have more resistance at TDC, again causing more stress to the parts mentioned above.
When your engine is properly tuned, it runs better for a reason. 190-200 degrees is not sufficient. You should at least be hitting 230 degrees.