Answer stability round 1: the readField comment names both directions of the shared value, and readName drops what namedPick states

pick.go

@@ -141,11 +141,11 @@ func (sc renderScope) frameOf(scope *nameScope) *pickFrame {
 	return nil
 }
 
-// readName reads a from its name's pick in the frame rendering the name's scope. Every read of
+// readName reads a from its name's pick in the frame rendering the name's scope. A read entering
-// one pick stays on it: the pick keeps each path's value and variant in its memo and its rows in
+// another category takes the frames of the name scopes there from the pick's memo (enter), and
-// its pins. A read entering another category takes the frames of the name scopes there from the
+// renderFrame finds them and opens none, so every read of the pick reads one pick of each name
-// memo too (enter), and renderFrame finds them and opens none. So {a.street} and {a.postal-code} in
+// bound there: {a.street} and {a.postal-code} in data/sv_SE/address.json read one pick of the
-// data/sv_SE/address.json read one pick of the name l that data/geo/SE/address.json binds.
+// name l that data/geo/SE/address.json binds.
 func readName(s *drawstate.State, sc renderScope, a arm) readValue {
 	f := sc.frameOf(a.named.scope)
 	if f == nil {

pick_test.go

@@ -333,7 +333,7 @@ func TestAColumnReadingABoundColumnIsThatColumn(t *testing.T) {
 	}
 }
 
-func TestAFreshReadInsideANamedPickReadsNoneOfThePick(t *testing.T) {
+func TestAFreshReadInsideANamedPickSharesNoValueWithIt(t *testing.T) {
 	f := engine(5)
 	src := `{"format":"{w as p}{p.a}|{p.a.b}","w":{"format":"{a}","a":{"format":"{c}|{b}","b":["1","2","3"],"c":{"format":"{b}","b":["x","y","z"]}}}}`
 	want := regexp.MustCompile(`^[xyz]\|([123])\|([123])$`)

render.go

@@ -145,8 +145,8 @@ func expand(s *drawstate.State, t *template, sc renderScope) string {
 // readField renders one arm of a token. A read of a name, or of a level a read of the name
 // rendering addresses, is kept in that name's pick; every other read draws afresh, so {word}
 // {word} draws twice and {p.a} {p.b} reads two draws of p. A fresh read leaves the pick: a read
-// below it would key the pick's memo by sc.pickKey, the level the pick rendered, and read the
+// below it would key the pick's memo by sc.pickKey, the level the pick rendered, so it and the
-// pick's value for a node the pick never drew.
+// pick would read one value for two nodes.
 func readField(s *drawstate.State, t *template, sc renderScope, a arm) readValue {
 	switch {
 	case a.kind == namedRead: