You could be on to something regarding water, Keith. I always make sure my mash pH is correct (between 5.1-5.5), but I don't do much water adjustment beyond that. One of my issues with my dry AIPAs is that the hop bitterness just isn't very pleasant -- it's too harsh. A lacking mineral composition could be having an effect on the quality of the bitterness.
My most recent hop profile for AIPA was:
.33 oz Centennial, .33 oz Cascade, .33 oz Amarillo (FWH)
.50 oz Columbus (60 min)
.33 oz Centennial, .33 oz Cascade, .33 oz Amarillo (30 min)
.33 oz Centennial, .33 oz Cascade, .33 oz Amarillo (15 min)
.33 oz Centennial, .33 oz Cascade, .33 oz Amarillo (1 min)
.50 oz Centennial, .50 oz Cascade (dry hop)
O.G. 1.062, IBU 67
On the other hand, my water is almost perfectly suited for many German beers. Alts and Helles turn out particularly well with virtually no water adjustment.