Hatto became famous very late in life when unauthorised copies of commercial recordings made by other pianists were released under her name, resulting in high praise from critics.
A critic for The Times wrote of a performance at Chelsea Town Hall in October 1953 that "Joyce Hatto grappled doggedly with too hasty tempi in Mozart's D minor piano concerto and was impeded from conveying significant feelings towards the work, especially in quick figuration.
Vernon Handley, who conducted the Guildford Philharmonic on Hatto's 1970 recording of Sir Arnold Bax's Symphonic Variations for her husband's Revolution label, said; "[a]s a solo pianist, she was absolutely marvellous.
"[7] Still the record received a favourable review: "Joyce Hatto gives a highly commendable account of the demanding piano part," wrote Robert Layton (Gramophone, February 1971).
In 1973 Hatto gave the world premiere of two recently published Bourrées by Frédéric Chopin in London's Queen Elizabeth Hall.
[14] From 2003 onwards the recordings attributed to Hatto began to receive enthusiastic praise from a small number of participants on various Usenet groups, mailing lists and web forums,[15] sparked by a blind-listening test in December 2002 posted on ThePiano Yahoo!
Godowsky group[24] that, in Hatto's version of the Chopin-Godowsky Studies on the Concert Artist label, a misreading of a chord was identical to one on the Carlo Grante recording (AIR-CD-9092, released 1993).
In particular, some found it hard to believe that a pianist who had not performed in public for decades and was said to be fighting cancer should produce in her old age a large number of recordings, all apparently of high quality.
The doubters were vigorously countered, most publicly by critic Jeremy Nicholas who in the July 2006 issue of Gramophone, challenged unnamed sceptics to substantiate their accusations by providing evidence that would "stand up in a court of law".
Nicholas's challenge was not taken up and in December Radio New Zealand was able in all innocence, to re-broadcast its hour-long programme of glowing appreciation of the Concert Artist Hatto CDs.
This programme included excerpts from a telephone interview with Hatto herself, conducted on 6 April 2006, in which she said nothing to dispel the presenter's assumption that she was the sole pianist on all the CDs.
The favourable reviews and publicity generated substantial sales for the Concert Artist CDs: in 2006, one online retailer did £50,000 worth of business with Barrington-Coupe.
After careful comparison of the actual Simon performances to the Hatto, it appeared to me that 10 out of 12 tracks showed remarkable similarity in terms of tempi, accents, dynamics, balances, etc.
At James Inverne's suggestion, Andrew Rose [of the audio-restoration business Pristine Audio] contacted me, and I uploaded three MP3s from the Hatto Liszt disc.
[33] The editor of Gramophone, James Inverne, commissioned an intensive investigation of the Hatto CDs by audio experts including Andrew Rose.
Within a week of the initial story being posted on the Gramophone website on 15 February, the sources for some 20 of Hatto's Concert Artist CDs had been identified.
[40] Robert von Bahr of the BIS label said that he "had given a lot of thought" to suing Barrington-Coupe for damages but was inclined not to do so on the assumption that the hoax recordings were "a desperate attempt to build a shrine to a dying wife".
[44] Barrington-Coupe was still alive at the time, but Wood stated in an interview with The Guardian that she did not consult him when she was writing the screenplay, although members of the research team for the project had met with him on a number of occasions.
The solo piano repertoire of these releases shows works Hatto played also at that time in London on various occasions at the Wigmore Hall and other venues.