diff --git a/modules/mesh-build-go/cmd/mesh-build-go/pins.go b/modules/mesh-build-go/cmd/mesh-build-go/pins.go
index d8b2f05f..a4452e41 100644
--- a/modules/mesh-build-go/cmd/mesh-build-go/pins.go
+++ b/modules/mesh-build-go/cmd/mesh-build-go/pins.go
@@ -10,6 +10,7 @@ package main
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -106,10 +107,14 @@ func (m *Module) resolvePins(ctx context.Context, root, dir, failure string) (bo
 	}
 	progress := false
 	for _, p := range forgePins(string(raw)) {
-		if !unknownRevision(failure) || !strings.Contains(failure, p.short) || strings.Contains(done, "replace "+p.module+" =>") {
+		if !strings.Contains(failure, p.short) || strings.Contains(done, "replace "+p.module+" =>") {
 			continue
 		}
 		where, err := m.placePin(ctx, root, p, failure)
+		if errors.Is(err, errNotAHead) {
+			// On no pull request head: go's failure is the caller's, in go's own words (issue 1748).
+			continue
+		}
 		if err != nil {
 			return false, err
 		}
@@ -121,8 +126,15 @@ func (m *Module) resolvePins(ctx context.Context, root, dir, failure string) (bo
 	return progress, nil
 }
 
+// errNotAHead is a pin whose commit no pull request head of the forge carries, when go's failure was not go knowing no
+// such revision: the failure is the network's or the forge's, and the caller says it in go's words (issue 1748).
+var errNotAHead = errors.New("on no pull request head")
+
 // placePin finds the commit of a pin among the pull request heads of the forge, places the repository at it beside
-// the workspace (the way a fetch places a sibling) and answers the directory of the module in it.
+// the workspace (the way a fetch places a sibling) and answers the directory of the module in it. **Whether a commit is
+// a head is the forge's fact** (issue 1126 review 2), never read from go's words: a group's check may have no name lookup,
+// and go then fails on the network before it can say it knows no such revision. go's failure only labels a commit on no
+// head: an unknown revision is said so, any other failure is errNotAHead, the caller's to say.
 func (m *Module) placePin(ctx context.Context, root string, p pin, failure string) (string, error) {
 	repository := "novox/" + p.repo
 	r := m.Run(ctx, []string{"GIT_TERMINAL_PROMPT=0"}, "git", "-c", "credential.helper=", "ls-remote", m.remote(repository), "refs/pull/*/head")
@@ -137,6 +149,9 @@ func (m *Module) placePin(ctx context.Context, root string, p pin, failure strin
 		}
 	}
 	if commit == "" {
+		if !unknownRevision(failure) {
+			return "", errNotAHead
+		}
 		return "", fmt.Errorf("the pin of %s at commit %s is on no pull request head of %s on the forge; go said: %s", p.module, p.short, repository, causeLine(failure))
 	}
 	// One placement per repository and commit, shared by every go.mod directory of the tree that pins it.
diff --git a/modules/mesh-build-go/cmd/mesh-build-go/versions.go b/modules/mesh-build-go/cmd/mesh-build-go/versions.go
index d580c04f..726319b6 100644
--- a/modules/mesh-build-go/cmd/mesh-build-go/versions.go
+++ b/modules/mesh-build-go/cmd/mesh-build-go/versions.go
@@ -17,6 +17,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"maps"
 	"os"
@@ -102,16 +103,18 @@ func (m *Module) takeVersion(ctx context.Context, root, dir string, tv *TakenVer
 	_ = json.Unmarshal([]byte(r.Stdout), &info)
 	if r.Status != 0 || r.Err != "" || info.Version == "" || info.Error != "" {
 		// Not a commit Go can fetch: the head of a group's pull request (ADR 0573 §4), placed from the forge's heads.
+		// Whether it is one is the forge's fact (placePin), whatever go said.
 		failure := strings.TrimSpace(info.Error + "\n" + r.Err + "\n" + r.Stderr)
-		if !unknownRevision(failure) {
-			// A download that failed for another cause (the forge or the resolver did not answer) says nothing of the pin: it
-			// fails with go's own words, and not as a kind the builder holds until the module changes (issue 1748).
-			return fmt.Errorf("downloading the asked version %s of %s failed (a download failure that may be retaken): %s", tv.Asked, tv.Package, causeLine(failure))
-		}
 		repo, sub, _ := strings.Cut(strings.TrimPrefix(tv.Package, forgePrefix), "/")
 		p := pin{module: tv.Package, repo: repo, sub: sub, short: tv.Asked[:12]}
 		pins.Lock()
 		where, err := m.placePin(ctx, root, p, failure)
+		if errors.Is(err, errNotAHead) {
+			pins.Unlock()
+			// On no head, and go failed for another cause (the forge or the resolver did not answer): it fails with go's own
+			// words, and not as a kind the builder holds until the module changes (issue 1748).
+			return fmt.Errorf("downloading the asked version %s of %s failed (a download failure that may be retaken): %s", tv.Asked, tv.Package, causeLine(failure))
+		}
 		if err == nil {
 			err = m.replaceInModfile(dir, tv.Package, where)
 		}
@@ -270,8 +273,8 @@ func comparePre(a, b string) int {
 }
 
 // unknownRevision says whether a go failure is go not knowing the revision (cmd/go's "unknown revision" and the
-// "invalid version" it wraps it in): the only failure that means a commit no tag or trunk holds, which may be the head of a
-// pull request. Every other failure is the network's or the forge's.
+// "invalid version" it wraps it in): it labels a commit the forge holds on no pull request head (placePin), and decides
+// nothing; every other failure is the network's or the forge's.
 func unknownRevision(failure string) bool {
 	return strings.Contains(failure, "unknown revision") || strings.Contains(failure, "invalid version")
 }
diff --git a/modules/mesh-build-go/cmd/mesh-build-go/versions_test.go b/modules/mesh-build-go/cmd/mesh-build-go/versions_test.go
index 00c82a64..b5288c37 100644
--- a/modules/mesh-build-go/cmd/mesh-build-go/versions_test.go
+++ b/modules/mesh-build-go/cmd/mesh-build-go/versions_test.go
@@ -20,6 +20,7 @@ import (
 func TestAnAskedVersionIsWrittenIntoTheModfileWhateverGoModNames(t *testing.T) {
 	const sdk = "git.novox.be/novox/mesh-sdk/go"
 	trunk := strings.Repeat("a", 40)
+	offHead := strings.Repeat("b", 40) // a commit no pull request's head carries
 	for _, c := range []struct {
 		name, asked, answer string
 		failing             bool
@@ -35,11 +36,16 @@ func TestAnAskedVersionIsWrittenIntoTheModfileWhateverGoModNames(t *testing.T) {
 		{name: "a group's head Go cannot fetch", asked: commitSHA, failing: true,
 			answer: `{"Path":"` + sdk + `","Error":"invalid version: unknown revision ` + pinShort + `"}`,
 			built:  commitSHA, said: "placed from the pull request's head"},
-		// The wording of go's errors: "unknown revision" is in cmd/go/internal/modfetch/coderepo_test.go; the lookup and
-		// connection texts are those of issue 1748's report and of the dial errors go prints for an unreachable forge.
-		{name: "a lookup that times out is no pin", asked: commitSHA, failing: true, failsWith: "i/o timeout",
-			answer: `{"Path":"` + sdk + `","Error":"git.novox.be/novox/mesh-sdk/go@` + commitSHA + `: dial tcp: lookup git.novox.be on 10.10.0.3:53: read udp 10.10.0.3:42292->10.10.0.3:53: i/o timeout"}`},
-		{name: "a refused connection is no pin", asked: commitSHA, failing: true, failsWith: "connection refused",
+		// Whether a commit is a pull request's head is the forge's fact, never read from go's words (issue 1126 review 2):
+		// a head is placed whatever go said (the group's check has no name lookup, so go fails on the network first), and
+		// go's words only label a commit on no head. The wording: "unknown revision" is cmd/go's
+		// (modfetch/coderepo_test.go); the lookup and connection texts are those of issue 1748 and the check of 12:42.
+		{name: "a head go cannot even look up is placed", asked: commitSHA, failing: true,
+			answer: `{"Path":"` + sdk + `","Error":"git.novox.be/novox/mesh-sdk/go@` + commitSHA + `: dial tcp: lookup git.novox.be on [::1]:53: connection refused"}`,
+			built:  commitSHA, said: "placed from the pull request's head"},
+		{name: "a lookup that times out is no pin", asked: offHead, failing: true, failsWith: "i/o timeout",
+			answer: `{"Path":"` + sdk + `","Error":"git.novox.be/novox/mesh-sdk/go@` + offHead + `: dial tcp: lookup git.novox.be on 10.10.0.3:53: read udp 10.10.0.3:42292->10.10.0.3:53: i/o timeout"}`},
+		{name: "a refused connection is no pin", asked: offHead, failing: true, failsWith: "connection refused",
 			answer: `{"Path":"` + sdk + `","Error":"git ls-remote -q origin in /tmp/gopath: dial tcp 10.10.0.1:443: connect: connection refused"}`},
 	} {
 		t.Run(c.name, func(t *testing.T) {
@@ -78,8 +84,8 @@ func TestAnAskedVersionIsWrittenIntoTheModfileWhateverGoModNames(t *testing.T) {
 			st := states.waitEnd(t)
 			if c.failsWith != "" {
 				if st.State != delivery.StepFailed || !strings.Contains(st.Reason, c.failsWith) || strings.Contains(st.Reason, "no pull request head") ||
-					!strings.Contains(st.Reason, "may be retaken") || delivery.FailedUntilChanged(st.Reason) || h.ran("ls-remote") {
-					t.Errorf("the download failure ended %s: %q (ls-remote ran: %v)", st.State, st.Reason, h.ran("ls-remote"))
+					!strings.Contains(st.Reason, "may be retaken") || delivery.FailedUntilChanged(st.Reason) {
+					t.Errorf("the download failure ended %s: %q", st.State, st.Reason)
 				}
 				return
 			}