I had a good percentage of Citrandarin cuttings root for me this summer. Seven out of ten is pretty good I think.
I was chatting with Greg from Maine and he mentioned it might have been due partly to the time they had in the fridge (four weeks) to callus over without getting dehydrated, but were still exposed to air. Also, during the rooting process, our temps were in 90s in the day and 80s at night.
We had a cooler early August and I did not see as many root. Then the weather turned warm again and few more rooted.
So I think heat, and a good callus without too much moisture are really important factors.
[/img]