1) Focus fusion is not the same as Dr. Bussard's approach. I contrast the three main approaches to hydrogen-boron fusion--focus fusion is one, the IEC that the late Dr. Bussard worked on is another.
2) There is a quantum effect of very high magnetic fields that reduces the efficiency of heating of electrons by ions but not of ions by electrons. This leads to much lower electron temperatures than ion temperatures, and thus much lower x-ray emission. It does not rely on non-equilibrium plasma.
3) This effect is based on well-established physics and has received experimental confirmation in z-pinches.
4) The reason why the next focus fusion experiment could cost as little as $2 million is because all work with the plasma focus device is very economical. The device can be built for only a few hundred thousand dollars. That is why there are DPF research teams in many developing countries that could not afford a bigger fusion machine.