This is a shame, because both of the Gary's make good points.
To my mind it is often the case with glass that things are more fluid (pardon the pun!) than we would like to think, making dating far more difficult than any of us would wish.
Millarart makes an assertion based on interviews with Chic Young which is fair comment and indeed adds to our knowledge on the subject, which to my mind gives it some importance. Conversely, Gary points out what has been the received wisdom prior to the Ysart Conference, and I guess one should add Millarart's reported interviews. Neither are wrong with their information, however it seems that there is a locking of horns about how to interpret that information that frankly boils down to 'Ya pays ya money and ya takes ya choice'.
Having said this I do have to add a little more information that is, I believe, already in the public domain. Ian Turner owned (from memory) maybe three pieces of Monart that were signed with an inscribed mark 'Paul Ysart'. They were made for an exhibition by Paul. Certainly one (and here again memory fails since it could have been more) was a well swirled piece, suggesting that Millarart's interviews with Chic Young are borne out. That is not to say Gary's assertions about the use of swirls before the war are wrong. It just helps amplify the information we are discussing.
At the Ysart Conference we were told that these swirls were known as 'Ysart Swirls' because they are synonymous with the Ysart family and their direct successors. It is difficult, if not impossible, to think of anyone using these swirls that cannot be linked back to the Ysarts - certainly up to around 2010, if not to date.
Nigel