This is true. When you mod the unit experience requirements you will notice that it's based on the number of kills the unit gets.Nobody seems to have mentioned unit size as a contributing factor. I first started playing with small units which needed a lot of battles to earn even one chevron (unless the unit was almost completly depleted). Now i play with large units and I have a 2 chevron unit (half depleted though) already after only 3 battles. Almost every unit that goes one-on-one with a enemy unit until it (enemy unit) routs seems to earn there first chevron.
So if it requires 40 kills to get your first chevron, you can get that much easier on huge than normal.
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