I worked on the Jade Splits yesterday evening with the extremely flexible Abbie as our instructor. Trying from Butterfly certainly gave more room for getting a flatter split, but my shoulder didn't think much of it. If you have a shoulder willing to play though I'd recommend it as a deeper way into the splits.
From Butterfly was also, just going to say, pretty scary :p I had Abbie holding me from below (which was brave since I was SUPER sweaty.....sorry Abbie xD).
Anyway - one week progress on the splits looks like this!