Interesting development here, ducted injectors inspired by ye olde Bunsen burner:
www.scientificamerican.com/article/can-diesel-finally-come-clean/
Potentially retro fittable too.
Common rail or even unit injection will still leave it behind. It's missing the ability to inject at different points of the combustion cycle. Might be a nice retrofit to an old engine, but it's still yesterdays technology.