Postcognition is probably fine, but you're offering potentially 3 Tiers and a Major Advantage to two separate stats which is better than we allow basically any technique at any cost (certain very costly techniques that are exclusive to a village (the Hachimon come to mind) may break that). Here
are provided some basics on boosting. I'll tell you that basing a boost to a stat on another stat's advantages will probably always be frowned on.
I'll mention that the flavor you're describing doesn't seem to have anything to do with Ref/Coo, but with Wis. I'll also mention that two other eye-based clans from canon (Hyuuga and Uchiha) also have a fairly minor increase to Wisdom (which as you may or may not know involves precognition). You will probably have a very hard time with this, in general. Directly increasing precognitive dodges is a no. If you want to increase precognitive dodges, increase your Wisdom. I'm not sure if it's intentional, but it would be very easy to simply get 4/4 with this clan's wording by just choosing Boss Stat and Wisdom, and it will never be our intention to approve anything that allows someone to dodge without recourse 100% of the time (meaning that even if someone less knowledgeable approves something that would allow this, it would be revoked if it were attempted to be used in that fashion). Hope this helps.
_________________We are not brave
We are not wise
We stand at the end of the longest lines
But we stand here all together
We have been damned
We have survived
We came back to homes we don't recognize
But we return here all together