diff --git a/rc_shared.sh b/rc_shared.sh
index 0ec806c..d03c404 100644
--- a/rc_shared.sh
+++ b/rc_shared.sh
@@ -1035,6 +1035,7 @@ function pv-test {
 									# Can be done like this if not changing over or under.
 									#bitrate="-b:v $vbr"
 
+									# Prefer this method so we know we're doing VBR (rc=1) not CBR (rc=2).
 									# rc=1, over defaults to 25, under defaults to 50
 									# rc=2, over defaults to 25, under defaults to 25
 									bitrate="-svtav1-params rc=1:tbr=${vbr}${o}${u}"