Continuous Hopping...What's the rational?

Just wondering what the rational is for continuous hopping. I've seen the practice recommended more than once, and am wondering what the benefits are.

For example, if you can get XX ibu from pitching X amount of hops at 60, 45, 30, and 10, why do a continuous pitch? I'm referring specifically to IPAs.

I don't doubt there's some flavor or other improvement, just curious as to what the theory is.

Sam Calagione of Dogfish Head Brewery is one of the major proponents of continuous hopping. He claims that it gives Dogfish Head IPAs (60 minute, 90 minute) a smoother, more balanced bitterness and more flavor. The bitterness would come from additions throughout the boil instead of having a bittering addition and late flavoring/aroma additions.

That said, I think that you can brew an IPA that is balanced in bitterness and flavor without continually hopping the beer. Others opinions may vary.

The rationale for the continuous hopping is that at each time in the boil, the hops will impart a certain aspect that is only attainable at that juncture. I haven't continuously hopped for a full boil, but I have from 20 minutes to flameout. The idea is that the 20 minute will be mostly flavor, but possibly a little aroma. 19 minutes is mostly flavor but a little more aroma, and so on until it's all aroma. Sort of like instead of sharp distinctions between white (flavor) and black (armoa), you get all the whole grayscale in there as well. There would be a natural smoothness from getting a little of both in the in between additions.

Doing this for the entire boil would have a smooth transition all the way from bitter, to flavor, to aroma.

Ahh so. I figured it was something along those lines. When I do my IPA I'll have to give this a go.

Some people say it is a gimmick but heck - doing anything else during a boil??

My feeling is that hops don't instantly react in boiling wort so throwing them in at 10 minutes or 11 minutes makes no difference. Even pellets take some time to 'dissolve' in the wort. I think it's more gimmick than anything.