It would be interesting to know exactly what the Dean and Chapter of Exeter had heard about their new bishop in August 1327. They certainly knew that he had been 'supplied' by the Holy See in place of the man they had themselves elected and whom the King had confirmed. Presumably they knew he was a favourite of Pope John XXII. I suspect they had also heard that he was a micromanager, because they immediately put in hand the creation of a new Cathedral inventory.
John de Grandisson (pronounced Grahns'n) certainly turned out to be a man who devoted scrupulous attention, and considerable funds, to worship. After his enthronement (which as a devotee of the Mater Misericordiae he fixed for the Octave Day of the Assumption in 1328; he decreed that the day should be a top-ranking feast for ever) his first decree endeavoured to raise the level of devotion among the Cathedral clergy by granting ample indulgences to those who devoutly attended choir and bowed their heads at the Names of Jesus and Mary. (It didn't work; hearing a few weeks later that the junior clergy were still behaving like naughty third-formers, he sent the Dean a stinker: 'Someone has failed to take measures ...').
As the first of his many benefactions, he gave a monstrance to the Cathedral so that Corpus Christi, recently (in effect) instituted by John XXII, could be properly observed with a procession. He began his great masterpiece, the Ordinale Exoniense, codifying and modernising the usages of his Cathedral (not, as one scholar has written, of the Diocese; in a time of manuscript altar-books the concept of diocesan regulations is anachronistic). He suppressed some dreadful old lyrics which had previously been sung in the Exeter Procession of Relics: Grandisson preferred the cults of the Blessed Sacrament and of our Lady to the telling of the dubious miracles performed by obscure relics. He dealt expeditiously with a false claim of a miracle, and suppressed a phony shrine of our Lady (in Fr Hummerston's parish) which was in effect a scheme for fortune-tellers to exploit the gullible. We have a couple of pages from a Mary Missal, for daily use in the Lady Chapel either at Exeter or at his collegiate foundation at Ottery, in which the bishop in his own handwriting has painstakingly corrected scribal errors. He completed the building of his Cathedral in great splendour. He went after a Cornish heretic who, like an American atheist academic recently, had stolen a Host specifically in order to commit sacrilege.
After his death he ordered that his obit be kept on the day after the Octave of the Assumption; that is, today. Cuius animae propitietur Deus.