I corrected two inaccuracies in my original post, I had done 10 days in the secondary not two with my raspberry wheat. Raspberries really aren't a subtle fruit, 1lb per gal lets the fruit shine in a lightly hopped beer. I have no idea how well it would work in a IPA. FYI Jamil tried a Pineapple IPA and said it was terrible, and recommended fruiting low to moderately hopped beers (Jamil Show, Fruit Beers 4-26-06).
I'd still recommend .5lbs per gal as a starting point, anything less I think will end up being completely lost.