A tie's curvature should scale with the horizontal distance between its noteheads, not use one fixed shape for every span

Short ties are drawn as a tight, shallow curve close to the notehead; a tie spanning a longer horizontal distance is drawn flatter (and slightly deeper) so it reads clearly without colliding with anything above or below. Unlike most rules in this domain, engraving authorities describe this as a matter of hand/engraver judgment rather than a fixed numeric law.

Ross discusses adjusting tie curvature proportionally to note spacing as routine hand-engraving practice.

Gould gives no numeric formula for this — Gradus should treat any threshold here as a tunable heuristic, not a cited hard rule.

Our own judgement, not a sourced convention — shown separately so the two are never confused.

This rule is about where marks land on the page, so it can only be judged after engraving. Collision and spacing faults live here.