There´s a very relevant information there:
“Fearless and Down range do not stack. If one was to take both perks only Fearless effects would be active”
I imagine that it´s a mistake and that Illfonic should correct it.
I think that all perks must work with their accumulated effects (stack).
Otherwise, there should be a disclamer pointing out incompatible perks if used at the same time.
I created a new topic on Bug Report for this: One perk is disabling the other