Originally Posted by mtb_addict

Sweaty back can be minimized by using those framed hiking backpack with a standoff mesh.
I use one by Aldi ($10)...it is only 10-liter...but it's just enough to carry my summer work cloths.

The OP has a fast road bike, and putting a rack on a road bike is just a pita...having to deal with p-clamps or seat post clamp. And with heel strikes, aerodynamic penalty, and extra weight.
I just don't like it on a road bike.