I've ridden my Pinarello Treviso many times in group rides but I myself would not want to race in a criterium with downtime shifters. If I'm going to sprint, I'm shifting early. No way am I winding it up over 20mph and then taking one hand off the bars to shift to a higher gear. While the pros undoubtedly have grande cojones, I am not willing to risk mine for simply bragging rights until next week.
If you go read biography's of sprinters, you'll see they often only shifted once in the sprint finish. They were already in a high gear, saving the highest for the last bit of the sprint. Partly because they knew their rivals could hear them shift and be forewarned.
Pros were/are capable of almost anything but mere mortals have the sense to stand back and survey the situation. If you have the skills, go for it. If you are unsure, then don't.
As somebody way below mere mortal, I am damn glad for brifters.
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