diff --git a/7t_trt/README b/7t_trt/README
index 2be1e9a08..d12e2e80c 100644
--- a/7t_trt/README
+++ b/7t_trt/README
@@ -1 +1,5 @@
 7t_trt data
+
+Demonstrates:
+
+- inheritance principle Example 5 on use of a single entities-less `physio.json`
diff --git a/7t_trt/task-rest_acq-fullbrain_run-1_physio.json b/7t_trt/physio.json
similarity index 100%
rename from 7t_trt/task-rest_acq-fullbrain_run-1_physio.json
rename to 7t_trt/physio.json
diff --git a/7t_trt/task-rest_acq-fullbrain_run-2_physio.json b/7t_trt/task-rest_acq-fullbrain_run-2_physio.json
deleted file mode 100644
index 21f78c192..000000000
--- a/7t_trt/task-rest_acq-fullbrain_run-2_physio.json
+++ /dev/null
@@ -1 +0,0 @@
-{"StartTime": 0, "SamplingFrequency": 100, "Columns": ["cardiac", "respiratory", "trigger", "oxygen saturation"]}
\ No newline at end of file
diff --git a/7t_trt/task-rest_acq-prefrontal_physio.json b/7t_trt/task-rest_acq-prefrontal_physio.json
deleted file mode 100644
index 21f78c192..000000000
--- a/7t_trt/task-rest_acq-prefrontal_physio.json
+++ /dev/null
@@ -1 +0,0 @@
-{"StartTime": 0, "SamplingFrequency": 100, "Columns": ["cardiac", "respiratory", "trigger", "oxygen saturation"]}
\ No newline at end of file