I tried on of the structured interval workouts today and it required me to go from, I think, 130w to 320w AND BACK in ten seconds flat while also somehow holding the 320w for a full ten seconds. Crazy, and I obviously could not do it. I do like to follow plans closely, though, so could you set workouts up so that they take account of such minor real-world factors as the need to accelerate and decelerate while changing gears?
Just go as hard as you can for the 10 seconds. If you’re on a smart trainer there’s no need to change gears. If you’re on a dumb trainer then get the gearing right about 10 seconds before the sprint. The reality is you’ll hit something like 360 watts and then taper off after the initial rush. So long as you gave it everything don’t worry if you got the star or not.