You can't tell the future and if you have anything to go by look at the iPhone 5 doubling in performance over the S3. Obviously Apple knows what they are doing when they can get a dual core to double a quad core with the A6.
But all they have done is produce a chip based on established ARM designs, tweaked it and put in a GPU made by another company. Then they have Samsung manufacture the chip for them.
And in the benchmarks I've seen the Quad Core Samsung S3 beats the iPhone 5 in some CPU benchmarks but loses miserably on browser performance tests and GPU performance. This isn't such an amazing feat when you consider the A6 is brand new out and the CPU in the S3 is already a year old. The Nexus 4 already beats the iPhone 5's performance and Google is touting it as the fastest phone in the world with regards to processor performance.
The point I was getting at before is Intel is the lead chip designer in the world they have billions of dollars to spend on it and it is almost all they do. Even car manufacturers know you can't design the entire car yourself you use engines and tires from other companies whose business is specific to that task.
Even Apple knows this which is why they've partnered with Motorola, IBM, ARM and Intel for their processors and chipsets over the years.
To be honest I think this rumor is a load of rubbish. Intel's Haswell chips are looking to bring wattage down to under 10 watts next year with performance much higher than any ARM design around. Even something custom made by Apple. And Intel has the benefit of being 64-bit from the start with built in killer graphics.