I'm generally opposed to technological fixes that are implemented while underlying problems aren't fixed. That's why I favor controls on black soot emissions: a likely measurable effect on warming and a simultaneous health benefit.
Plus, there would have to be some good pilot-project (no pun intended) research on this idea to prove that it works and doesn't cause unintended bad environmental consequences. But I don't think the idea should be dismissed out of hand. I also don't think we're at a stage where it's necessary. I may think differently in 20 years.
There is a great deal of uncertainty what the underlying problem is, if indeed there is a problem. Black soot, however, is certainly undesirable, but you are in error to link it to global warming.
But I do like the idea of black soot controls. Basically, the United States leads in this area. Such controls add to the cost of manufacturing. If third world nations are required to live by the same environmental standards that we are forced to live by, then we would be competing on a more level playing field.