What's going on here might be more than just an effort to "detoxify the brand." It's what we saw in Disraeli's "one nation" Toryism, Bismarck's creation of the welfare state and in the Tories' acceptance in the 1950s of most of the welfare state built by the 1945-51 government - an attempt to buy off discontent.
Yes, the Tories are the party of the rich. But it is not always in the collective interests of the rich to get immediately even richer.This aim must be balanced against the aim of ensuring the social stability which allows the rich to stay rich in future. As James O'Connor wrote:
The capitalistic state must try to fulfill two basic and often contradictory functions - accumulation and legitimization...This means that the state must try to create or maintain the conditions in which profitable capital accumulation is possible. However, the state also must try to maintain or create the conditions for social harmony. (The Fiscal Crisis of the State, p6)
Osborne and Montgomerie fear that a backlash against inequality might lead to support for harsher redistributive policies which hinder capitalist accumulation. So they want to enact such policies on their own, milder terms. It's a form of vaccination: introducing a small amount of the disease of redistribution can protect the capitalist organism against the bigger disease of even greater equality.
Insofar as the Tories have been successful down the decades, it's because they've been able to balance accumulation and legitimization; Thatcher stressed the former, Disraeli the latter, but they are two legs of the same beast.
This raises two questions. First, how strong are the material pressures on the Tories to adopt a more egalitarian stance? I'm in two minds here. On the one hand, working class power is sufficiently weak that it can be ignored, which means there's little need to "bribe the working classes", in Bismarck's phrase. But on the other hand, the social norm against corporate tax-dodging is strong, and the hope that enriching companies would encourage investment and growth seems to have been dashed - both of which point to the need for more legitimization policies.
Secondly, if redistributive policies can be adopted by the "right" (eg Disraeli, Bismarck), and if they can be shunned by the "left" under pressure from capital (eg New Labour), could it be that we over-rate the importance of the colour of the government, and under-rate that of the social norms and class power which constrain governments? At least some economic research (pdf) suggests the answer might be: yes.