You don't need to know any technology, it's easy to see if you have common sense. If this approach is workable. The fact is, we are still running single processor computers with more and more stages. The increase in pipeline depth is proven to be much slower than the clock rate. Not to mention multiple processor.
Engineering is all about cost-saving.
And sociologically, if a certain application, like real-time radiosity rendering, can only be done with two or more processors, few will do it. Therefore, they can wait until one day a single processor can do that. Or they can develop a specialized chip to do so, like MPEG encoding. It will be very expensive to make a low-end x86 processor to encode in real time, so they developed some cheap circuits. Apple users can't live without very basic common sense.