I don't think looking at the time frame between parks of the past and how that might pan-out for parks in the future is quite practical.
Even if you look at it as, they built 4 parks in 30 years... so the 5th one being in 20 years makes sense. That's basically saying "In 100 years they'll build 5 more!"
I didn't say it was defacto evidence of anything, but just that it's not crazy to think that in ten years it's a possibility was the point, since we will be more than two decades without one. Which is why I don't think it's as much of a gamble to predict as some might.
I've met Jim, he's a nice guy and he does love Disney. I don't think he does things maliciously. Having said that, I tend not to give much weight to what he writes. I see him more as an entertainment writer.
I don't think most people think he is malicious, but that he simply all about self-promotion. Now that he's over at HuffyAOLversion he has let his site pretty much die off, as people stopped going there after listening to him promise the a thanksgiving feast and instead end up delivering a ham sandwich too many times.
The problem is, with adding the mythical "fifth gate" to Walt Disney World, is that adding the fourth gate (DAK) didn't really spread crowds out in the Magic Kingdom like it should have.
No one argues that is what happened, but they key is -
why it happened.
It was because the marketing of the park was extremely confusing, and while it's a pretty park (undoubtedly, though even that is slightly overrated - I mean, it's all jungle, with various styling of faux-dilapidated buildings - without the names on the buildings it's hard to tell which "land" you are in as they are all so similar) the live animal experiences are much better elsewhere in regional zoo's, and there aren't many "attractions" to keep repeat visitors coming back.
I mean, there is no attraction in AK that couldn't fit into another park - it really has little identity of it's own besides "it's in the jungle". I mean, look how they are shoehorning Avatarland in there - because of it's "conservation" theme. They might have well have said it's because Nuvi or whatever they are called are Blue and humanoid so they are animals since humans are a species of animals in the sense of living beings. And if Avatar becomes the signature attraction? We are pretty far from "Animal Kingdom" at that point.
Now, if they came up with a rock'em, sock'em theme for a park - something to really wow people - then that would be much different. However, because of the knee-jerk backlashers, I won't go further into detail about what I really think would bring attendance up at WDW, but I am sure Disney knows all too well what is missing in the experience that they provide at the WDW resort.