To be fair, Shellhammer hasn't conducted this experiment on a New England IPA as far as I know. Although your recipe doesn't show it, you would generally add your dry hops well before fermentation is complete. This could be anywhere from high krausen to 8-10 points from final gravity, but definitely when you still see active fermentation. The theory is that there are biotransformations of hop compounds into other fruity aromatics that occur when using specific yeasts. However, on a practical level you're also losing some of the VOCs to CO2 scrubbing.
16 oz in dry hop per 5 gallons is a ton of hops, but I use 8oz regularly in this style.