Managed a sort of start on the Gloria while (seated) on the train yesterday morning; and it may wind up scuttled, and if so, you know the finished piece will justify the call.
This morning, the thought occurred to me, of writing optional interludes for brass quintet. Haven't decided one way or t'other.
I think I will, after all, start by tweaking (making sure the Altos are not invited to sing anything patently uncomfortable) the Credo, and adding rehearsal reduction where necessary. And then, to the Gloria.