Even if you assume it is true, there's also an assumption that you have to build the crappy 80% along with the good 20%. Otherwise, we'd just build the 20%, right? But wait, then it would be 100%.
You can call it 80-20, but building the crappy 80% is just part of the deal. You're still back to 100% of your pages making 100% of your income.
Even using the 80-20 thing, you still double your pages (or sites) to double your income.
Using one page as an example isn't really real world. Could we also say that 20% of that one page makes 80% of the income for that page? If so, you still have to write 100% of the page.
The rest of the original post gave me plenty to think about that I might not have otherwise. Thanks.