How many cells of each type did you cycle? Every cell is different, so it could just be that the one (or two) you cycled at 1 A/g had less homogeneous electrode surfaces, which wouldn't be visibly noticeable.

It could be that the calendaric degradation also plays a role here (2 A/g cycling requires less time for the same cycle number compared to 1 A/g) So maybe take a look at the capacity over time?

Thanks @sebasteinKlick