Should out/ref parameters require the caller to specify out/ref like in C#?

[Nicholas Wilson via Digitalmars-d]

On Sunday, 28 May 2017 at 17:54:30 UTC, WebFreak001 wrote:
> Imagine you wrote a function
>
> void foo(ref int a) {
>   if (std.random.uniform(0, 10) == 0)
>     a = 0;
>   // Actual code doing something
> }
>
> [...]

It seems nice in theory but how will it interact with generic 
code?
Perhaps it should be optional and purely documentative.