No one's denying Newtonian mechanics. But we are dealing with very marginal differences. You obviously know that certain things are not negotiable for your riding and you will sacrifice lightness to maintain those things. I know what matters in my riding too -- and weight really isn't one of those things that's high on my list. Hydration, ability to make common repairs on the road in the middle of nowhere, durability, stiffness, a stable ride, minimal flat tires, smoothness, great shifting ... these are the things that I look for and will without hesitation sacrifice weight for.