Good question Bill
Trimark posts paramater guidelines from 75-95% argon balence C02
http://www.hobartbrothers.com/pdf/datasheets/Metalloy70X.pdfThey say it can be both short arc and spray...
I would hazard to speculate that the same gas mixes for solid wire would probably produce similar transfer to the cored wires.....
If it sprays you ought to be able to see the pinch effect ..... Not very scientific but hey... D1 considers cored wire and solid wire pretty much the same anyhow.