Again posting here even though I haven't raced in years.
Years ago (about 10) when I was in my late 50's I was on a team ride leading to chase down a break for a city limit sign. I didn't know that I was in my 39 tooth chain ring and pushing a 15 tooth cog and still going 34 mph. My teammates said that I looked smooth.
There was a reason why in the old days racers trained some on fixed gear bikes. Back then you didn't have as much flexibility when selecting gears and shifting under load was much more iffy, You had to be able to perform with suboptimal gearing.
I also understand why junior gearing is employed. It is to teach proper pedaling and not just stomping on the pedals.