It is clearly not a system of "winner takes all", but one in which winners take a fair sum for their results (i.e. they actually win when they win), and the numbers of winners is maximised. These winners then help create more opportunities for others and the system provides the aligned incentives to maximise successes. The adoption of more capitalism has enriched the world, and in India and China, markets have enabled a greater number of people to escape poverty, than government planning ever will.
The record of history is clear, and the temptations must be avoided. Now is the worst time to pursue theories, that when implemented, even in part have produced and would require terrible oppression, economic stagnation, the destruction of freedom; failure in almost all regards, with the honourable exception of the production of hard liquor to substitute for water and null the pain. Under variants of socialism and communism, there were more deaths than in all the wars of the 20th century (as a direct result of government oppression) and under all significant indicators, these experiments failed to compete with the freer nations.
Optimism tells us that Mr Cameron argued for moral capitalism, as an appeal to popular opinion, rather than because of misguided beliefs. The threat against free people, free markets and freedom is always great, and the tide must not turn. Moral Capitalism is just plain simple Capitalism.