Consecutive same-voice rests must consolidate to the single largest legal rest value whose onset is aligned to that value's own metrical grid

Adjacent same-voice rests that together exactly fill a metrically-recognized window consolidate upward into the single largest legal rest symbol for that window: two eighth rests starting on a quarter-beat boundary become one quarter rest; three eighth rests starting on a compound-beat boundary (e.g. the start of a 6/8 beat) become one dotted-quarter rest — but the same two eighth rests starting mid-beat (not on a quarter-grid position) do NOT consolidate to a quarter rest, because that would misrepresent where the beat falls, exactly mirroring the dot-onset-alignment logic for notes.

Two consecutive eighth rests occupying the entirety of beat 2 in 4/4, left unconsolidated as two separate `e` rests instead of one `q` rest; or in 6/8, a full compound beat of silence written as `e,e,e` instead of the single `q.` rest.

Gould, Behind Bars, ch. 'Rests', the consolidation table by meter; Ross, The Art of Music Engraving, preferring fewer, larger rest symbols for legibility.

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