Yes, it's somewhat banally true, but it's an important subset of the language because the guarantees of transitively-safe Rust represent a baseline for what you can ultimately guarantee in the language. Work like Patina (ftp://ftp.cs.washington.edu/tr/2015/03/UW-CSE-15-03-02.pdf) is useful for that reason. Transitively-safe Rust may also independently fulfill a useful role in the language; e.g., it is a candidate for the subset acceptable in constant expressions.