For those who may not know (and assuming I have got it right), Paul Hollister (Jr.) is well known in paperweight circles for his 1969 book "The Encylcopedia of Glass Paperweights".Your assumption are right it is one and the same person, though I did misspell his name.
But more importantly, he was a leading light (at least, in the USA) in the field of studio glass, having written many articles from the 70s thru 90s. See: http://www.bgc.bard.edu/news/events/-91.html
For those people who don't know who Betty Reid was. Betty worked all her working life at Moncrieff glassworks and single handed saved so much Monart archive materail from getting put in the skip when Monart finished production in 1961, which is now in Perth museum.
I believe though not certain, that the four marked pontil was used on the applied foot of Monart pieces.
so nigel was correct then regarding concave pontils , also there are examples of monart with the four marked pontil, I have one somewhere and I know keith has some also , or is this a different thing their on about
My goodness, thanks very much for sharing those letters with us Gary How very gratifying, my feelings have been chuffedGlad to be of some assistance.