Great thread.
I'm in the camp where my road bike is so much faster and comfortable that I have gone to great lengths using it for me 26-mile RT commute, including leaving my laptop at work or enduring the sweat of a backpack (yuck). My laptop won't fit in a saddlebag.
The seat clamp looks brilliant - I'll order one right away. But is it possible not adapt a regular rack (I use a Topeak) for the QR mount?