diff --git a/tools/Python/mctest.md b/tools/Python/mctest.md
index 9e7d15896..5d92bdeb8 100644
--- a/tools/Python/mctest.md
+++ b/tools/Python/mctest.md
@@ -21,9 +21,13 @@ target value per scan point, which may span several header lines:
       86.04,101.892,108.731,...,
       85.406 }
 
-`mcrun`/`mxrun` and `*.instr` tokens on test lines are ignored. A scan uses its
-own `-n` if given, otherwise at most `1e5` per point, and runs its points in
-parallel (`--scan_split=auto`) unless MPI is used. A value, or every point of a
+`mcrun`/`mxrun` and `*.instr` tokens on test lines are ignored. A `%Test:`
+always runs at the global `--ncount` (scaled by `--statfactor`): a `-n` on its
+line is only a hint for users (`mcdoc` shows it) and is ignored, with a log
+message. To get better statistics in a `%Test:`, change the instrument (e.g.
+`SPLIT`) rather than adding `-n`. A scan uses its own `-n` if given, otherwise
+at most `1e5` per point, and runs its points in parallel (`--scan_split=auto`)
+unless MPI is used. A value, or every point of a
 scan, passes when it is within 20 % of its target, or, with `--nsigma` or
 `--pvalue`, within the statistical tolerance described below.
 
diff --git a/tools/Python/mctest/mctest.py b/tools/Python/mctest/mctest.py
index cfaa111c7..2efcaaaef 100644
--- a/tools/Python/mctest/mctest.py
+++ b/tools/Python/mctest/mctest.py
@@ -117,6 +117,8 @@ def create_instr_test_objs(sourcefile, localfile, header, noscans=False):
     #   Detector: NAME_I=2.00752e+08 NAME_ERR=2.28872e+06 NAME_N=50752 "NAME.L_U1"
     for m in re.findall(r"\%(?:Example|Test):([^\n]*)Detector\:([^\n]*)_I=([0-9.+-e]+)([^\n]*)", header):
         parvals, ncount = split_test_line(m[0])
+        if ncount:
+            logging.info("%s: -n%s on a %%Test/%%Example line is ignored, the test runs at the global --ncount" % (sourcefile, ncount))
         detector = m[1].strip()
         err = re.search(r"%s_ERR=([0-9.+-eE]+)" % re.escape(detector), m[3])
         tests.append(InstrExampleTest(sourcefile, localfile, parvals, detector, float(m[2].strip()), len(tests) + 1, ncount=ncount,
@@ -567,6 +569,7 @@ def mccode_test(branchdir, testdir, limitinstrs=None, instrfilter=None, compfilt
         # told to use the default values (-y can not be combined with
         # parameter values, since the instrument then ignores those):
         parvals = test.parvals if test.parvals else "-y"
+        # A %Test/%Example always runs at the global ncount (its own -n is ignored).
         # A %Scan uses its own -n if given, else at most 1e5 pr. point, and runs
         # its points in parallel unless MPI already does that within each point
         testncount = ncount