When Egwene sees Gareth Byrne for the first time after he has been bonded she notices the deadly grace if a warder in him.

This seems to imply that this deadly grace is a direct result of the bond. I always presumed that the deadly grace was the byproduct of of a decade plus of hand to hand combat fighting and training. That warders were the elite of the elite of randland.

Added to this, Aiel have often been described as moving like warders.

Does this mean that anyone bonded instantly becomes more graceful and deadly?

Laras? Bran al'Vere? An innkeeper?

Or is this an error on Sandersons part? (or mine?)