David Millar would be with you, right up until you suggest ditching the FD.Maybe I'm just being mischievous here; you decide.
If you're really into TTs, and never use the 39t, why not ditch it and run a single chainring, saving the weight of the unused ring, the FD, the control cable and maybe fit a lighter rear brake lever, as you no longer need the indexed changing mechanism? As a bail-out gear, maybe run a slightly larger top sprocket on the cassette.