Personally, i see it was a optional mechanic for when stealth is not an important factor but the area he is in is still dark.
If stealth is important or you would not prefer using a ''monster magnet'' torch, then by all means consume a cat potion. But know that it increases Geralt's toxicity level and obviously it consumes both the valuable potion and the ingredients used to make it.
If stealth is important or you would not prefer using a ''monster magnet'' torch, then by all means consume a cat potion. But know that it increases Geralt's toxicity level and obviously it consumes both the valuable potion and the ingredients used to make it.