I don't know what attempts are being made in the muggleborn camps, although we'll keep our ears open for any hints of people trying it. I do know though that Davidson's people were particularly interested in that last Grim Truth, and they have several teams working on practising the spells suggested. Only a very few have managed to have much luck channelling their power, although, of course, those two or three people are very excited about the possibilities. But apparently, it takes a great deal of practice.