There are closely related "MHV amplitudes" which naively obey a really complicated formula, but for which there famously also exists a much simpler "Parke-Taylor formula". Alfredo had derived a complicated expression for these new "single-minus amplitudes" and we were hoping we could find an analogue of the simpler "Parke-Taylor formula" for them.
Thank you for taking the time to reply, I see you might have already answered this elsewhere so it's much appreciated.
My pleasure---thank you for your interest!