Parameters declared as the alias of a template won't accept the arguments of the same type.

[Elfstone via Digitalmars-d-learn]

    module test;

    struct MatrixImpl(S, size_t M, size_t N)
    {
    }
    template Vector(S, size_t N)
    {
        alias Vector = MatrixImpl!(S, 1, N);
    }

    @nogc
    S dot1(S, size_t N)(in Vector!(S, N) lhs, in Vector!(S, N) 
rhs)
    {
        return 0;
    }

    @nogc
    S dot2(S, size_t N)(in MatrixImpl!(S, 1, N) lhs, in 
MatrixImpl!(S, 1, N) rhs)
    {
        return 0;
    }

    unittest
    {
        import std.stdio;

        Vector!(float, 2) a, b;
        dot1(a, b); // Error: none of the overloads of template 
`test.dot1` are callable using argument types 
`!()(MatrixImpl!(float, 1LU, 2LU), MatrixImpl!(float, 1LU, 2LU))`
                    // Candidate is: `dot1(S, ulong N)(in 
Vector!(S, N) lhs, in Vector!(S, N) rhs)`
        dot2(a, b); // compiles
        static if (is(Vector!(float, 2) == MatrixImpl!(float, 1, 
2)))
        {
            writeln("WTH"); // prints
        }
    }

It's natural to declare it the way dot1 is declared, isn't it?
Is this a bug?
Or I simply can't assume alias works the way I thought it would.
Can I work around it, without falling back to the abominable dot2?