diff --git a/tests/kernel-cases/README.md b/tests/kernel-cases/README.md
index cef8d505b..2c3a95c0d 100644
--- a/tests/kernel-cases/README.md
+++ b/tests/kernel-cases/README.md
@@ -107,7 +107,7 @@ cargo xtask kernel-cases --ladder --kernel both --cli target/release/solidcraft-
 cargo xtask kernel-cases --ladder --kernel both --cli target/release/solidcraft-cli --record "why"
 ```
 
-`--record` measures one case at a time, rewrites the golden and sorts each tier by the first
+Ladder runs measure one case at a time (unless `--jobs`); `--record` rewrites the golden and sorts each tier by the first
 kernel's time, fastest first; commit both files. The report, `docs/kernel-ladder.md`, gives per
 tier and kernel the counts per status and the **frontier**: the first case in ladder order the
 kernel fails.
diff --git a/xtask/src/kernel_ladder.rs b/xtask/src/kernel_ladder.rs
index 97f23a211..39fa07243 100644
--- a/xtask/src/kernel_ladder.rs
+++ b/xtask/src/kernel_ladder.rs
@@ -5,8 +5,8 @@
 //! areas). Each case is a test like any rig case, graded against its own `expected.json`. On top,
 //! `tests/kernel-cases/ladder/golden.json` records per case and kernel the status, the commands'
 //! time and what the kernel made (counts, volume, area): the run compares with it and flags
-//! slowdowns and changes. `--record REASON` re-measures the golden (one case at a time unless
-//! `--jobs` says otherwise, so the times are not shared with other cases) and re-sorts each tier
+//! slowdowns and changes; cases run one at a time unless `--jobs` says otherwise, so the times are
+//! not shared with other cases. `--record REASON` re-measures the golden and re-sorts each tier
 //! by the first kernel's time, fastest first; both files are committed.
 //!
 //! The report, `docs/kernel-ladder.md`, gives per tier and kernel the counts per status and the
@@ -264,7 +264,9 @@ pub fn run(rest: &[&str]) -> Result<(), String> {
         Some(Some(r)) => Some(r.to_string()),
     };
     let mut o = options(rest)?;
-    if reason.is_some() && !rest.contains(&"--jobs") {
+    // Times are compared with the golden: cases run one at a time unless --jobs says otherwise,
+    // so they don't share the machine with each other.
+    if !rest.contains(&"--jobs") {
         o.jobs = 1;
     }
     let manifest = read(&manifest_path());
diff --git a/xtask/src/main.rs b/xtask/src/main.rs
index ee0c5926f..3784bb785 100644
--- a/xtask/src/main.rs
+++ b/xtask/src/main.rs
@@ -54,8 +54,8 @@ commands:
                   every result as JSON too)
                   --ladder [--record REASON]: the complexity ladder instead
                   (tests/kernel-cases/ladder/ladder.json, tiers in order), graded and compared
-                  with its timing golden, into docs/kernel-ladder.md; --record re-measures the
-                  golden one case at a time and re-sorts each tier by time
+                  with its timing golden (one case at a time unless --jobs), into
+                  docs/kernel-ladder.md; --record re-measures the golden and re-sorts each tier by time
   action-matrix [--bless] [--results FILE] [--from DIR]
                   try every ordinary action on every face, edge, vertex and body of the design
                   corpus and compare with tests/action_matrix/baseline.json (--bless rewrites it;