An engineered solution to global warming?

I read an interesting article today about some research by a German Nobel prize winning climatologist. His thesis was that it would be possible to reverse the effect of global warming by increasing the volume of sulpher in the stratosphere. The sulpher would reflect solar energy in much the same way that large pyroclastic eruptions cause sulpher to become trapped in the troposphere to similar effect. In fact they say that the eruption of Mount Pinatubo led to a 0.5 degree reduction in average global temperatures in the following year. Professor Crutzen estimate the annual cost of an engineered solution to be $12.5bn and $25bn per annum.

This thesis in itself is interesting. However, what seems more interesting to me is the moral dilemma: Are we now reaching a point where global consensus towards CO2 emissions reduction is beyond redemption and therefore a reactive solution should be encouraged? Or, by so doing, are we appeasing the industrial realpolitikers and therby ringing the death knell of multilateral emissions reduction? Can geo-engineering research co-exist with a global emissions control agenda?