In 1958 Davis was at his early peak, his playing marked by a beauty of tone and a perfection of line which brought him the affection of an audience far beyond his regular jazz constituency.
His use of a flugelhorn in place of his usual trumpet for most of Porgy and Bess merely enhanced the almost unbearable loveliness of his sound, while Evans' orchestrations, which could be either lean and unsentimental or warmly seductive, provided a matchless setting.
For many years, however, this was destined to be music with no life outside the recording studio. Unbelievably, only on a handful of occasions were Davis and Evans provided with sufficient funds to perform their collaborations in concert. By the time the value of their music became clear even to the most dim-witted promoter, both men had moved on, so the initiative shown by Scott Stroman and the jazz orchestra of the Guildhall School of Music and Drama in searching out Evans' elusive manuscripts and preparing them for concert performances results in many kinds of stirred emotion.
Few can have hoped to hear this music again in any but its recorded form; indeed, the suite had never before been played in its entirety to a live audience.
If it is asking a great deal of student musicians to live up to such a legacy, then their pleasure in the privilege of inhabiting the structures of this music was easy to appreciate and admire. But can its spirit be inhabited by any group of musicians not under the direct control of Gil Evans?
This is the sort of question confronting all those who wish to make a living repertoire out of the music of the great jazz composers of the past.
So faithfully and sensitively did the orchestra perform the suite last night, all the way from the fevered fanfare of "Buzzard Song" to the jaunty farewell of "There's a Boat That's Leaving Soon For New York", that the highest possible compliment would be to say that there were moments when the music seemed to be playing itself, reanimated once more by Evans' unique spirit.
All the trademarks of colour and texture were given full value: the weightless woodwind combinations, the calm French horns, the quick stabs of muted brass, the daring use of unison tuba and double bass as a combined lead voice - all of these completely new to jazz 40 years ago. And in the impossible role of Davis himself, the veteran American trumpeter Randy Brecker gave a skilled and generous interpretation of some of the most famous lines in jazz.
A little more prone to displays of virtuosity and self-conscious bluesiness than Davis himself, perhaps, but if this music were about exact imitation then it would have no value. A labour of love then, and received in kind.