DR John G, I worked for John Yap a lot, and I have good and not-so-good thoughts about most of his recordings. I like the KISS ME, KATE, which followed John McGlinn's recording on EMI, and I prefer the TER leads much more than McGlinn's Josephine Barstow and Thomas Hampson. I love love love Diana Montague, and it was her work for John Yap on the KATE and SONG OF NORWAY that prompted me to ask her to record ROBERTA in 2013.
In Diana's defense, since I think she has the right voice and talent to play the role, I don't think either John - McGlinn or Yap - is a great director of actors; McGlinn controlled the performers far too much and stifled the life out of many of them, and, since I was only in a couple of sessions with him, I suspect Yap doesn't give the actors enough direction.
My biggest complaint with the TER recordings is that there's not enough homework before recording. For example, both the TER GREASE and KISS ME KATE suffer from using laundered lyrics in the published vocal scores that were cleaned up for high schools to use. McGlinn's KATE has the uncensored lyrics and the wonderful Kim Criswell and George Dvorsky, although I like all of the TER cast as well.
All that said, there are many TER recordings I like quite a lot and they include the KATE and GREASE.
