Misconception discussion: T is a superset of both &T and &mut T

[wodny]

While it's true and can be presented with generics, maybe a note that the following is possible would be beneficial, so nobody erroneously extrapolates the rule:

struct Foo();
trait Trait {}
impl Trait for Foo {}
impl Trait for &Foo {}
impl Trait for &mut Foo {}

Like with impl Read for TcpStream and impl Read for &TcpStream.