I caught myself daydreaming yesterday after contemplating a DFH 90-minute clone. I was thinking about what the result would be if you paired the "late hopping" technique (as described in Gordon Strong's new book "Brewing Better Beer") with the continuous hopping technique popularized by the well-known DFH recipes. I guess it wouldn't EXACTLY be a simple pairing of the two techniques, but more of an emphasis on continuous hopping by dividing your entire hop bill into precisely timed additions (say maybe an addition every 5-minutes during a 60-minute boil). The idea would be to increase each addition by a certain amount, so that if you had a graphic image of all the additions in your mind it would look sort of like a staircase.
I'd love to hear your thoughts on the idea. If you've actually tried something like that and have a store to tell, even better!