Adding more micro-threads per core increases dramatically load on microprocessor's shared resources.
The technology is designed to achieve speeds of up to 2.5GHz per core, while minimising power consumption.
Nehalem provides a 15-20% clock-for-clock increase in performance per core(average)
There is at most one running process per CPU or core.
The expected performance of floating point per core would be approximately 1.8 times that of the K8 family, at the same clock speed.
In September 2009 they published a roadmap that instead showed 8 threads per core.
Allow half a pear per person, peel and core then, and cut each in half.
Simultaneous multithreading by multiple cores and hyper-threading (2x per core).
Hyper-threading (2x per core, starting from 5518), that was already present in pre-Core Duo processors.
The biggest problem is that huge amounts of commercial server software is now licensed per core.