@RiotMeddler Why doesn't Quinn's Harrier get reduced to 3 seconds?

The wiki says: "Valor periodically marks a nearby enemy with Harrier Vulnerable for 4.5 seconds. This cannot occur again for a few seconds, decreasing if Quinn triggers the Vulnerable (ON-TARGET COOLDOWN: 10 / 3)."

However, I've just tested it and Harrier always seems to go on a 5-6 second cooldown after triggering it (interpreting both ways as proccing the harrier, as well as applying harrier via vault). Now it seems the static 5-6 second cd is a compromise to the supposed 10/3 second cooldown, but the 10/3 cooldown is far better. Why? It makes 25% CDR so much more enticing. With 25% CDR and the 3 second reduction, we'd have a steady flow of: double harrier->single harrier->double harrier->single harrier, since 25% CDR would put vault on a 6 second cooldown.

So did Harrier get some change that was undocumented? Or is this just a long-standing bug? I hope its the latter.