Well this has been a long and interesting conversation. I was in search of info on mash hopping since I now have a recipe for zoigl. In this recipe you only boil for 5 minutes so there would be no bitterness, just flavor and aroma. I was going to step mash but the gentleman who gave me the recipe is a big fan of decoction so I'm thinking that is why he was getting some bitterness in his beer. It was a wonderful beer when his brewery was open, too bad the management screwed it all up!
As far as FWH, I did this with my first IPA and loved it. You thought the hops were done tickling your tongue then 20 seconds later, BAM, you got hit with some more! We called it Aftershock IPA and it was a great beer. Need to do that again!