diff --git a/README.md b/README.md
index 38fc02a..fee24e1 100644
--- a/README.md
+++ b/README.md
@@ -5,5 +5,6 @@ A relatively simple example wrapper working (kinda) as a *by-value* `dyn Trait`.
 Limitations:
 * The wrapper size is fixed. The content either fits, or it doesn’t compile.
 * Supporting each trait requires a bit of code, as there is no way to express “for each *trait* X” in Rust.
+* Like with `Box<dyn _>`, you can’t call by-value methods on the content.
 * Requires unstable features (notably `ptr_metadata`, others are probably avoidable).
 * `unsafe` here, `unsafe` there, `unsafe` everywhere! (It does pass Miri though).