It's easy to get swayed by a brewing fad, especially if you're a new brewer. The appeal of continuous hopping (adding 1/16 oz. of hops every minute) or brewing radically (mushroom, raspberry, chipotle, lemon zest pale ale) or brewing SMaSH beers and expecting amazingly complex character.
While not as ridiculous as the previous fads, I personally think FWH is a fad for the "American IPA" style. This style is supposed to be bitter with a little bite to it. If you want to lessen that bite, then use less bittering hops, or none at all, with a lot of late aroma hops. You could even choose a lower cohumulone hop to ease the harshness.
No need to FWH the A-IPA style, and especially the A-IIPA style. FWH was established by German brewers to smooth out a lowly hopped style of beer (comparitive to the AIPA). But there is more than one way to skin a cat (or in this case to ease the bitterness relative to what your palate desires).
I've done FWH for a few IPAs and noticed that simply lessening the bittering addition made up for the difference. That way, you could save more of your hops for the aromatic late additions. For this style, it's really about the amount of initial IBUs you add to your wort, not FWH vs. Boil hops. 20-35 IBUs seems to be the sweet spot for that first addition if you want a less bitter IPA, whereas 40-60 IBUs at the start will obviously yield a more bitter IPA.
I'm a fan of LWH (Last Wort Hop) for American IPAs... Yes, I just invented that term. Or post-boil, whirlpool, flameout... whatever you wanna call it. Essentially- to steep the post-boil hops in the wort for at least 20 minutes in "warm" wort, instead of adding them directly at flameout in piping hot wort, which is no different than a 1, or maybe even a 5 minute boil addition.