I ride an aluminum road bike with steel fork, fenders and a rack. Yeah its heavier than a bike with carbon fork, and definitely heavier than a pure carbon race bike. But even with panniers and a trunk I can easily cruise at 14-17 in jeans after busting my butt at a very physical day job. Reaching 20mph isn't that hard if I'm trying either.

Now take off the trunk bag, panniers and wear my kit and a morning ride on my day off and I can blow the wheels off someone with a "faster" bike.

The bike won't make you go faster, that's your job.