Pin bare-reference independence and tighten the shared-draw comments

hold.go

@@ -274,8 +274,7 @@ func readField(s *session, t *template, held, shared *draws, a arm) string {
 		}
 		return renderShared(s, t.fields[a.key], shared)
 	}
-	// A reference names a shared source, so a record shares its draw across the
+	// A reference shares its draw across a record's columns; a sibling is per expansion.
-	// columns; a sibling field is drawn per expansion as always.
 	d := held
 	if isRef(a.key) && shared != nil {
 		d = shared

record_test.go

@@ -200,6 +200,32 @@ func TestRecordSharesAReferenceIntoAColumnRepeat(t *testing.T) {
 	}
 }
 
+func TestRecordBareReferenceStaysIndependent(t *testing.T) {
+	dir := writeData(t, map[string]string{
+		"currency": `[{"format":"{code}","code":"AUD"},{"format":"{code}","code":"EUR"}]`,
+		"order":    `{"format":"","whole":"{/currency}","code":"{/currency.code}"}`,
+	})
+	f := newGenerator(t, dir, WithSeed(1))
+	sawMismatch := false
+	for i := 0; i < 100; i++ {
+		r, err := f.Record("order")
+		if err != nil {
+			t.Fatal(err)
+		}
+		m := map[string]string{}
+		for _, c := range r.Fields() {
+			m[c.Name] = c.Value
+		}
+		if m["whole"] != m["code"] {
+			sawMismatch = true
+			break
+		}
+	}
+	if !sawMismatch {
+		t.Fatal("a bare {/currency} column never disagreed with a tailed {/currency.code} column; a bare reference should draw independently")
+	}
+}
+
 func TestRecordSQLQuotesIdentifiers(t *testing.T) {
 	dir := writeData(t, map[string]string{
 		"row": `{"format": "", "postal-code": "1", "street-number": "2"}`,

render.go

@@ -56,8 +56,7 @@ func render(s *session, n node) string {
 }
 
 // renderShared is render with a shared draw context: the draws a record shares
-// across its columns. A nil shared means a standalone render, where a reference
+// across its columns; a nil shared is a standalone render.
-// is drawn per expansion as it always has been.
 func renderShared(s *session, n node, shared *draws) string {
 	switch n := n.(type) {
 	case *choice: