Um, guys, not that difficult lol. Having a lower walk rate lowers WHIP because you'll have less walks per inning, and it lowers your FIP cause it's a DIPS stat, and a lower FIP results in a higher fWAR, so yeah, WHIP is correlated to fWAR. It has a -.473 or so r^2 (all individual seasons since 1947 min 50 IP). The lower the WHIP, the higher the fWAR, the higher the fWAR, the lower the WHIP.
They're correlated.