Suvival of the Fittest "the misconception"

In modern terms ‘Survival of the Fittest” is something of a buzz-phrase used to validate everything from corporate greed to the concepts of humanist belief systems. The first recorded use of it is thought to be by Herbert Spencer; a polymath or in today’s parlance, a Renaissance man.
He drew parallels between the economic theories he was working with and Charles Darwin’s ‘On the origin of Species’ in his ‘Principles of Biology (1863). He coined the term in many of his own writings on the subject of evolution; which, ironically he had written before Darwin.
He adopted a somewhat Lamarchian (Lamarckian Inheritance)bent believing that an organism can pass on traits acquired during its own life. Today in some circles, epi-genetics is reaffirming that possibility.
The Misconception of today’s interpretation ‘the survival of the fittest’, is Darwin’s usage of it as a synonym for natural selection, adapting Spencer’s term and using it in the fifth edition of ‘On the Origin of species published in 1869.
Of course Darwin meant it to be representative of an organism better adapted for its environment, not the accepted definition of being the best physically fit. For those pushing ‘survival of the fittest’ as a form of social Darwinism; closely aligned philosophically to Progressivism, they have totally lost the understanding of both Spencer and Darwin’s scientific intent as well as the efficacy of evolutionary theory. Most evidence relies on the cooperative aspects of human biology and although competition plays a part in individual competitions, there is little evidence that the great leaps of civilizational evolution; those steps forward, relied on competition, if anything the collaborative aspects of working together in balance with collaborative competitions seems to be more the poignant point.