"Enthusiasm is the great hill-climber." - Elbert Hubbard (1856 - 1915)
Gelato is geared relatively low (44 x 18, 66"), which is light on the knees, fast on the hills.
When I go riding with my geared buddies, I know I can't attack on the flats, 66" is not a big gear.
So I wait for the hills and then I attack.
Single speeds are faster for sure on the hills as compared to geared bikes (most of the time). This is where I gain time on my buddies.
Of course, they all catch me on the downhill, but that's life on a single speed my friends.
You take what the road gives you, no more, no less.