Old thread, but I wanted to chime in with my HH DIPA kit experience.
I picked up the extract kit and followed the directions exactly with the specialty grains and hop additions. However, I miscalculated the amount of ice I needed to chill the wort and ended up with 6 gallons in my fermenter!! This brought my OG down to about 1.067. I aerated by vigorously stirring with my drill mixer for several minutes and pitched two packs of Wyeast American Ale. Primary for 2 weeks @70 deg, racked into secondary and dry hopped for 1 week. After only 2 weeks in the bottle this beer is the best I've made so far. Although it was only my 4th completed batch. My FG ended up at 1.016 so my miscalculation turned this into an IPA as opposed to a DIPA--probably knocked the IBUs down a bit too--but still VERY drinkable!