Combine herbs, balsamic vinegar, molasses, and pepper in a medium bowl. Slowly stir in olive oil, and mix well. Add quail, stirring to coat quail evenly. Refrigerate overnight.

Put balsamic vinegar in a non-reactive pot, bring to a simmer over medium heat. Reduce heat to medium-low and reduce vinegar slowly to a syrup. Be aware that it is very easy to burn the vinegar, so pay attention.

Preheat grill to medium-high. Season quail with salt and pepper, and grill about 2-3 minutes on each side. Leg meat should feel firm. Keep warm. Serve with Balsamic syrup drizzled over.