diff --git a/doc/usage.md b/doc/usage.md
index 5aeef34479..f9e50908f3 100644
--- a/doc/usage.md
+++ b/doc/usage.md
@@ -192,4 +192,5 @@ require("6to5/register")({
 the `experimental: true` option when using the [Node API](#node) or
 `--experimental` when using the [CLI](#cli).
 
-**NOTE:** That these are subject to change as their proposal status progresses.
+**WARNING:** These proposals are subject to change so use with
+**extreme caution**.