Excellent solution 670cc! Now my question is how difficult is it to install a longer cable?
Depending on if there are any concealed cable anchors, you may be able to just tie the end of the new cable to the old cable with tape, and pull it through. If the cable is anchored tightly somewhere under the bodywork, then plastics removal would be necessary. I don't have a DCT model, so I don't know the specific details on the brake cable routing.