Consecutive full-bar rests in one voice should collapse into a single multi-measure rest with a bar-count numeral, which Gradus cannot currently express

When a voice rests for several consecutive complete bars, convention shows a single multi-measure ('gathered'/H-bar) rest spanning all of them with a numeral above indicating the count, rather than repeating the whole-rest glyph bar after bar. Authorities differ on the exact glyph for short runs: Ross documents an older hand-engraving convention of small grouped tick-marks for 2-4 bars before switching to the beamed H-bar symbol at 5+; modern engraving software (Dorico, Finale, LilyPond) uses ONE consistent H-bar-plus-numeral glyph for any run of 2 or more bars with no special-casing. RECOMMENDATION for Gradus: follow the modern-software convention (single glyph form for any count ≥2) since Gradus is a digital-first, screen-rendered tool with no hand-engraving legacy to preserve.

A voice authored with N consecutive whole-bar rests (e.g. a SATB alto voice tacet for 4 bars while soprano solos) renders as N separate whole-rest bars with no bar-count numeral.

Gould, Behind Bars, ch. 'Rests', multi-bar rests; Read, Music Notation, same; Ross, The Art of Music Engraving, documents the older tick-mark convention for short runs (an explicit disagreement, resolved above); SMuFL defines dedicated multi-rest glyphs distinct from the single whole-rest glyph.

This rule can be decided from pitches, durations and voices — no layout required. A validator can check it before anything is drawn.