Basically, rather than burning, they are advocating charring crop residues which leaves much (well, half) of the carbon. My gut tells me (warning: WAG ahead) that it would probably be more effective, and safer (less risk of starting an uncontrolled fire), to just leave the residue in place or let livestock clean it up. Letting a ruminant get much of it's diet from crop residue seems most attractive to me, but letting residue remain as a moisture conserving mulch makes a lot of sense too.

It would be interesting to see the approach in the article compared to the alternatives. Rather than just holding up an orange and saying, "Lood at this nice orange," we could compare it to the other oranges and apples.