A former Sumsion pupil writes that Sumsion's 'vision in matters of programme planning together with his skill of direction in a very wide spectrum of works made him one of the most successful conductors' in the Three Choirs Festival's history. From 1928 until his retirement in 1967, Sumsion was responsible for planning and serving as the principal conductor for eleven festivals held at Gloucester. Although Sumsion personally acknowledged the challenge that cathedral organists—who were primarily choral conductors—faced in conducting major orchestral works, his own conducting was greatly respected, and his interpretations of Elgar's works were viewed as being representative of the composer's own readings. At the first festival following Elgar's death (1934), Sumsion proposed that the three cathedral organists each conduct one of the Elgar works on the program, a welcome division of labour for the host conductor that would later become standard practice. After the retirement in 1949 of Percy Hull of Hereford and Ivor Atkins of Worcester, Sumsion remained the only direct link with Elgar amongst the musicians of the three cathedrals.