I recall SVCC giving a stunning recital at All Souls Langham Place a few years ago; Gerald Brooks gave her 'Kingsfold' to improvise on with spectacular results in what is a dry acoustic.
I did not attend the SPC recital-my loss-but I would have been irked with the choice of themes. An insult to both the artiste and audience. I recall a similar situation at Southwark some years ago when Naji Hakim was given 'London Bridge is falling down'
We deserve better. Improvisation is a serious discipline. Given that the likes of Choplin, Latry, Hakim and co spend week in and week out improvising on gregorian chant, this should be the basis of their imprvisation on the rare occassions that they give recitalls in the UK.