SYSML21 — Clarify Rules for Applying Dashed Outlines to Non-Composite Features

Problem 1: How to render referential usages outside their context

All examples in the spec show referential usages only in two situations:

Tree view — white diamond, "ref" keyword omitted from shape
Nested view — dashed border or «ref part» keyword

No example covers a referential usage shown standalone (not nested). For ports, the spec explicitly limits dotted lines to nested ports (8.2.3.12, p. 213), but no analogous restriction exists for parts/connections.

Problem 2: "ref" keyword shown inconsistently in shape across views

Same "Binding Connection" example from Table 11 renders three ways:

Implied rule: omit "ref" when referential nature is already conveyed visually (diamond or dashed border). Spec never states this explicitly.

Problem 3: Always-referential features rendered inconsistently

The spec defines several features as always referential regardless of the "ref" keyword:

Perform action usages — 7.17.1 (p. 87), 7.17.6 (p. 104)
End features (connection/interface ends) — 7.13.2 (p. 67)
Attribute usages — 7.7.2 (p. 46)

But in nested view examples they render differently:

Both are always-referential by definition, yet rendered differently with no rule given.