Is this only to be used in cases where lack of performance is a 100% (99%?) known thing, or where it's conceivable that a performance was arranged without the knowledge even of authorities on a composer (over a sufficiently long period of time? That is, should NoPerf be restricted to modern works of which it can be placed with some certainty, or can it also be used for manuscript works of older composers that have almost certainly also not been performed yet?) Eric 15:39, 28 March 2017 (CEST)