First-American IPA's are different than English IPA's.
American IPA's, at this time, have a massive aroma, and it's easier and more predictable to get this from dry hopping than by just dumping mass quantities in at flame out. It isn't the same outcome, in my opinion.
APA's are just a scaled down version of American IPA's, lower ABV, so less bittering, and a more moderate dryhopping, or course it isn't as necessary in the APA, as it is in an AIPA. But proportionally acceptable.
A general rule of thumb is like a 60-15/20-0 type of hop addition schedule for an AIPA, but continuous hopping, and all other sorts of variation are practiced.
It isn't the impact of the hop
flavor,
but more a very generous amount of smooth hop aroma that makes an AIPA talked about and revered.
The PNW has taken this to an extreme, the term 'hop bomb' comes to mind, and turned many off to the effect, but here in MI, the technique is alive and well, and is an expected part of the bottle opening, or first whiff of glass experience.
