diff --git a/mission/controller/ThermalController.cpp b/mission/controller/ThermalController.cpp
index 0ed8a4d9..6a624c62 100644
--- a/mission/controller/ThermalController.cpp
+++ b/mission/controller/ThermalController.cpp
@@ -215,6 +215,7 @@ void ThermalController::performControlOperation() {
     }
     heaterTransitionControl(heaterSwitchStateArray);
     heaterMaxDurationControl(heaterSwitchStateArray);
+    // This dataset makes the TCS CTRL observable.
     PoolReadGuard pg(&tcsCtrlInfo);
     for (uint8_t i = 0; i < thermalStates.size(); i++) {
       tcsCtrlInfo.heatingOnVec[i] = thermalStates[i].heating;