Small improvements don’t look like much. That is because they are, by definition, small. But they do add up. Just ask the 2018 Colts. They made a bunch of small improvements from 2017, and ended up in the playoffs and playing in the AFC Divisional Round.
One of those small improvements was blitzing at the right time. For much of the first half of the year, the Colts were one of the teams that blitzed the fewest of anyone. But in the second half, they used smart blitzes to confuse quarterbacks and put them under pressure.
Those pressure forced mistakes and allowed the Colts to take advantage of them.