Thanks Wheeze I would have been very surprised if nobody had done the PW both ways back to back I think Robin Price did it in 9 days 5hrs and 55 secs but like you I don`t know what time of year, and I suspect there are many others that have done it without documentation.
I don`t wish to try to make anybodys efforts seem less than they are, but for me a true winter round/traverse or any other achievement should be completed in the 2 weeks either side of the shortest day, but to achieve these feats with minimal daylight and possible bad weather always deserve recognition.