Important issues need a suitably monumental treatment and Stier draws comparisons with Mahler, one of three composers specifically acknowledged by Corigliano (the others being Berlioz and Shostakovich).
But though Mahler's particular musical mix might not get such a personal response in the concert hall, Corigliano "makes a real impact by using the musical language of today," Stier says.
He agrees the 40-minute work is an epic statement ("awesome in the real meaning of the word") and was touched by the effect it had on audiences in Germany, where he has conducted it six times.
"On one occasion a woman told me that, after leaving the hall, she was so moved that she didn't know whether to cry or scream."
In fact, Stier would prefer we look beyond the angry outbursts of the first movement, with its title, Of Rage and Remembrance. He points to the calmer third with its unabashedly romantic cello solo (inspired by the composer's friend Giulio, who played the instrument).
"It's in the major key, which is unexpected and effective," he says. "If it were to make me cry it wouldn't be through pain or anything terrible - I'd cry because it helps me to understand, as if God or a higher energy force is offering some explanation."
The weight of the Aids tragedy is inescapable. "Throughout the score, Corgiliano has written the names of his dead friends, from directors and computer designers to accompanists and critics," Stier says. "It's like wandering through a cemetery, meeting up with those who have gone before."
Though Stier himself has not experienced the sorrow of losing friends and colleagues to Aids, Corigliano's music offered comfort when his sister was killed in a car accident 16 years ago. "It's here that I found peace and consolation; it spoke powerfully for me in my time of need."
The German conductor is not the only ardent proponent of Corigliano's piece. Another is Ronan Tighe, the APO's manager of artistic planning, who first heard the symphony as a student in Dublin.
"The National Symphony did it and my roommate was engaged to play mandolin," he says. "We listened to the Barenboim recording at home and in the student common room. For me, at that age, it was quite something to hear music that told a story about where I was from as a gay man."
However, there is a universality to Corigliano's statement that also speaks to a wider world.
"This music is extraordinary," Tighe stresses. "Anyone who experiences it, either gay or straight, will be affected by it. It's a powerful testament to its times."
