diff --git a/CLAUDE.md b/CLAUDE.md
index ce29833..c263429 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -140,9 +140,10 @@ was the one that contained a real bug.
 **A skipped Gadfly run reports success.** A comment without the trigger phrase
 still starts the workflow, which logs `comment does not contain trigger phrase`
 and exits green in ~2 seconds. So "the pipeline is green" does NOT mean "this
-was reviewed". Confirm a re-review actually ran by checking that it posted a new
-consensus comment — or that the run took minutes rather than seconds — not by
-its status.
+was reviewed". Confirm a re-review actually ran by its **duration** — a real
+pass takes ~10 minutes, a skip takes 2 seconds. Don't look for a new consensus
+comment: Gadfly EDITS its existing status-board and consensus comments in place,
+so their `created_at` stays at the first review and only `updated_at` moves.
 
 Workflow- and config-only changes (CI, this file, docs) go straight to `main`
 without the PR dance.
diff --git a/internal/service/ops.go b/internal/service/ops.go
index 2fa05df..08e4b5f 100644
--- a/internal/service/ops.go
+++ b/internal/service/ops.go
@@ -214,10 +214,13 @@ type localPoint struct{ x, y float64 }
 // Do not "simplify" this back to anchoring at the region's min corner. That is
 // what #75 was: staggered rows start a full pitch in, and the leftover all lands
 // on the far edge, where clumps hang outside a bed that nothing clips them to.
-// It reports the total alongside the points, and works that total out BEFORE
-// building anything: a fill large enough to be refused shouldn't allocate its
-// whole lattice first just to be counted and thrown away. Over `limit` it
-// returns (nil, total) so the caller can refuse with the real number.
+//
+// # Counting before building
+//
+// hexCenters returns the total alongside the points, and works that total out
+// BEFORE building anything: a fill large enough to be refused shouldn't allocate
+// its whole lattice first just to be counted and thrown away. Over `limit` it
+// returns (nil, total), so the caller can still refuse with the real number.
 func hexCenters(r Region, radius, spacing float64, limit int) ([]localPoint, int) {
 	if radius <= 0 {
 		return nil, 0
@@ -259,7 +262,7 @@ func hexCenters(r Region, radius, spacing float64, limit int) ([]localPoint, int
 		// and centering THAT run puts it exactly half a pitch off its neighbours.
 		// A single-column region has nothing to stagger against.
 		if row%2 == 1 && cols > 1 {
-			n, x = staggered, r.MinX+x0+radius
+			n, x = staggered, r.MinX+x0+pitch/2
 		}
 		for i := 0; i < n; i++ {
 			pts = append(pts, localPoint{x + float64(i)*pitch, y})
@@ -276,6 +279,12 @@ func hexCenters(r Region, radius, spacing float64, limit int) ([]localPoint, int
 // A span too small to hold even one position at that inset still gets one, in the
 // middle: filling a bed narrower than a single plop with one plop is a better
 // answer than refusing to plant it.
+//
+// The step<=0 half of that guard is currently unreachable — hexCenters, the only
+// caller, returns early unless radius > 0, which makes both steps it passes
+// positive. It stays because dividing by a non-positive step yields ±Inf and then
+// a garbage int conversion, and a helper this small should not require reading
+// its caller to know it is safe. Deliberate, not an oversight.
 func fitAxis(length, step, inset float64) (n int, start float64) {
 	if step <= 0 || length < 2*inset {
 		return 1, length / 2