diff --git a/quic/interop/inspect-multiplexing.sh b/quic/interop/inspect-multiplexing.sh
index 81c948919..c5aa271c5 100755
--- a/quic/interop/inspect-multiplexing.sh
+++ b/quic/interop/inspect-multiplexing.sh
@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 # Pull the post-mortem diagnostics for the most recent multiplexing run.
 # Runs from anywhere; resolves logs relative to the runner clone path
-# you've been using (../quic-interop-runner from this repo).
+# (../quic-interop-runner from this repo).
 set -euo pipefail
 
 REPO_ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
@@ -12,7 +12,6 @@ if [[ ! -d "$RUNNER_LOGS" ]]; then
     exit 1
 fi
 
-# Most recent run dir.
 RUN_DIR="$(ls -1dt "$RUNNER_LOGS"/run-* 2>/dev/null | head -n 1 || true)"
 if [[ -z "$RUN_DIR" ]]; then
     echo "no run-* dirs under $RUNNER_LOGS" >&2
@@ -29,20 +28,12 @@ if [[ -z "$CASE_DIR" ]]; then
 fi
 echo "==> case dir: $CASE_DIR"
 
-echo
-echo "=============== file tree under case dir ==============="
-find "$CASE_DIR" -maxdepth 4 -type f -printf '%s\t%p\n' 2>/dev/null \
-    || find "$CASE_DIR" -maxdepth 4 -type f -exec ls -l {} + 2>/dev/null
-
-echo
-echo "=============== output.txt (runner stdout — last 200 lines) ==============="
-tail -n 200 "$CASE_DIR/output.txt" 2>/dev/null \
-    || echo "(no output.txt)"
-
 echo
 echo "=============== writer-side debug traces (DEBUG=1 build only) ==============="
-# Per-drain frame/budget stats from buildApplicationPacket. Empty
-# unless the image was built with `make build DEBUG=1`.
+# Per-drain frame/budget stats from buildApplicationPacket. The
+# smoking-gun section for "writer is iterating N active streams but
+# emits only 1 STREAM frame per packet". Empty unless the image was
+# built with `make build DEBUG=1`.
 WRITER_LINES=$(grep -c '\[writer' "$CASE_DIR/output.txt" 2>/dev/null || echo 0)
 if [[ "$WRITER_LINES" -gt 0 ]]; then
     echo "($WRITER_LINES writer trace lines; first 30:)"
@@ -54,96 +45,49 @@ if [[ "$WRITER_LINES" -gt 0 ]]; then
     echo "active histogram (active stream count at drain time):"
     grep -oE 'active=[0-9]+' "$CASE_DIR/output.txt" | sort | uniq -c | sort -rn
 else
-    echo "(no [writer.* lines — run with DEBUG=1 image: cd quic/interop && make build DEBUG=1)"
+    echo "(no [writer.* lines — rebuild image with: cd quic/interop && make build DEBUG=1)"
 fi
 
 echo
-echo "=============== server stderr (last 100 lines) ==============="
-tail -n 100 "$CASE_DIR/server/stderr.log" 2>/dev/null \
+echo "=============== server stderr (last 50 lines) ==============="
+# Peer's CONNECTION_CLOSE reason if any; processing pace via stream
+# create/discard cadence.
+tail -n 50 "$CASE_DIR/server/stderr.log" 2>/dev/null \
     || echo "(no server/stderr.log)"
 
-# Find the qlog. The runner mounts QLOGDIR=/logs/qlog so we land at
-# client/qlog/<odcid>.sqlog inside the case dir.
 QLOG="$(ls -1 "$CASE_DIR"/client/qlog/*.sqlog \
         "$CASE_DIR"/client/qlog/*.qlog \
-        "$CASE_DIR"/client/*.sqlog \
-        "$CASE_DIR"/client/*.qlog 2>/dev/null | head -n 1 || true)"
-
-if [[ -n "$QLOG" ]]; then
+        2>/dev/null | head -n 1 || true)"
+if [[ -z "$QLOG" ]]; then
     echo
-    echo "=============== qlog event-type histogram ==============="
-    echo "(file: $QLOG, $(wc -l <"$QLOG" | tr -d ' ') lines)"
-    grep -oE '"name":"[^"]+"' "$QLOG" | sort | uniq -c | sort -rn | head -n 20
-
-    echo
-    echo "=============== frames-per-packet histogram (sent) ==============="
-    # Smoking gun for "is the writer coalescing or sending one STREAM
-    # per datagram":
-    #   - Many `frames=1`  → regressed, one stream per packet on the wire
-    #   - Most `frames>=4` → writer is bursting, server is the bottleneck
-    grep '"name":"transport:packet_sent"' "$QLOG" \
-      | awk -F'"frame_type":' '{print NF - 1}' \
-      | sort -n | uniq -c
-
-    echo
-    echo "=============== stream-frames-per-sent-packet histogram ==============="
-    # Same shape but counts STREAM frames specifically (vs ack/ping/etc).
-    # A "stream" frame_type means request data going out.
-    grep '"name":"transport:packet_sent"' "$QLOG" \
-      | awk -F'"frame_type":"stream"' '{print NF - 1}' \
-      | sort -n | uniq -c
-
-    echo
-    echo "=============== first 10 packet_sent events (full) ==============="
-    # The very first stream-bearing packets reveal whether we burst
-    # the chunk's 64 streams OR dribbled them out one per RTT. Look
-    # at the `frames` array — if it has 13 stream entries, writer
-    # is bursting; if 1, writer is regressed.
-    grep '"name":"transport:packet_sent"' "$QLOG" | head -n 10
-
-    echo
-    echo "=============== first 10 packet_received events (full) ==============="
-    # If we sent N streams in burst, server should respond with N
-    # responses interleaved as it processes them. Spread tells us
-    # server-side serial cost.
-    grep '"name":"transport:packet_received"' "$QLOG" | head -n 10
-    # If initial_max_data is small (e.g. < 1000 bytes), our writer
-    # gets throttled to one stream per packet because connBudget
-    # exhausts after the first stream. Each subsequent stream has to
-    # wait for a MAX_DATA frame from the peer (1 RTT each).
-    grep '"name":"transport:parameters_set"' "$QLOG"
-
-    echo
-    echo "=============== peer MAX_DATA frame timestamps + values (received) ==============="
-    # If MAX_DATA frames arrive with small bumps and at one-per-RTT
-    # cadence, we're flow-control bottlenecked: peer extends credit
-    # by ~50 bytes per RTT, we send one stream per credit bump.
-    grep '"name":"transport:packet_received"' "$QLOG" \
-      | grep -oE '"frame_type":"max_data"[^}]*' \
-      | head -n 30 || echo "(no max_data frames in qlog — may need to upgrade qlog observer)"
-
-    echo
-    echo "=============== first 30 packet_sent stream offsets (per-stream byte count) ==============="
-    # If every stream emits exactly one ~50-byte chunk before the next
-    # stream starts, we're connection-flow-control bound.
-    grep '"name":"transport:packet_sent"' "$QLOG" \
-      | grep -oE '"stream_id":[0-9]+' \
-      | head -n 30 || echo "(no stream_id field in qlog — may need to upgrade qlog observer)"
-
-    echo
-    echo "=============== last 5 packet_received events ==============="
-    grep '"name":"transport:packet_received"' "$QLOG" | tail -n 5
-
-    echo
-    echo "=============== last 5 packet_sent events ==============="
-    grep '"name":"transport:packet_sent"' "$QLOG" | tail -n 5
-
-    echo
-    echo "=============== connection_closed events ==============="
-    grep '"name":"transport:connection_closed"' "$QLOG" || echo "(none — connection didn't formally close)"
-
-    echo
-    echo "=============== packet_dropped events (last 10) ==============="
-    grep '"name":"transport:packet_dropped"' "$QLOG" | tail -n 10 \
-        || echo "(none)"
+    echo "(no qlog under $CASE_DIR/client/qlog — skipping qlog sections)"
+    exit 0
 fi
+
+echo
+echo "=============== qlog ($QLOG, $(wc -l <"$QLOG" | tr -d ' ') lines) ==============="
+
+echo
+echo "stream-frames-per-sent-packet histogram:"
+# Many `0` = ack-only; many `1` = the bug; many `>=4` = writer
+# coalescing as intended.
+grep '"name":"transport:packet_sent"' "$QLOG" \
+  | awk -F'"frame_type":"stream"' '{print NF - 1}' \
+  | sort -n | uniq -c
+
+echo
+echo "transport_parameters (local + remote):"
+grep '"name":"transport:parameters_set"' "$QLOG"
+
+echo
+echo "first 10 packet_sent (full) — burst shape after handshake:"
+grep '"name":"transport:packet_sent"' "$QLOG" | head -n 10
+
+echo
+echo "connection_closed events (peer CCs are the smoking gun for spec violations):"
+grep '"name":"transport:connection_closed"' "$QLOG" || echo "(none)"
+
+echo
+echo "packet_dropped events (last 10):"
+grep '"name":"transport:packet_dropped"' "$QLOG" | tail -n 10 \
+    || echo "(none)"