I've been playing around with post-boil hop additions on a few different IPAs recently and adding a majority of the hops after flameout. Very interesting article on how this adds to IBU's and where it might start getting a diminished return on aroma. https://www.homebrewersassociation.org/how-to-brew/effect-post-boilwhirl...
Tue, Apr 4, 2017 - 8:08pm
#1
Good IPA read on Post-boil hop additions
So, I guess a flame out hop addition with a 10 minute whirlpool is the sweet spot (I skimmed the article.)
I'm still a fan of the 10-15 minute 'flavor' boil.