Yeah, a humidity dome of some sort is pretty essential.
I am totally willing to try this on a couple of test clones to see if they root better. Those are not bad roots for the time given.
I will also let some be exposed to a lower humidity right at the start to see if that encourages root growth. I have not tried either of those things and I am now curious.
I can foresee a block of 20 clones, 5 split and dried, 5 just dried, 5 just split. and 5 control.