Update README.md

Author: Tortar

README.md

@@ -24,15 +24,15 @@ This will generate:
 
 1. An immutable struct `S_Immut`;
 2. A mutable struct `S_Mut`;
-3. Constructors for `S` that can create either the mutable or immutable version.
+3. `const S = Union{S_Immut{Y}, S_Mut{Y}} where Y`.
 
 It is then possible to create instances of the specified version:
 
 ```julia
-julia> s1 = S(1, 2, 3.0; mutable=true)
+julia> s1 = S_Mut(1, 2, 3.0)
 S_Mut{Int}(1, 2, 3.0)
 
-julia> s2 = S(1, 2, 3.0; mutable=false)
+julia> s2 = S_Immut(1, 2, 3.0)
 S_Immut{Int}(1, 2.0, 3.0)
 ```
 
@@ -47,13 +47,8 @@ julia> @update s2.y = 3
 S_Immut{Int}(1, 3, 3.0)
 ```
 
-Importantly, there are some catches to keep in mind:
-
-- The constructors are backed by a dummy struct of the same name (e.g `S` in the example above) which means
-  that it would be incorrect to dispatch on it. Use one of the versions of the structs or the abstract type
-  instead;
-- For an immutable type, the mutation actually involve the creation of a new instance with
-  [Accessors.jl](https://github.com/JuliaObjects/Accessors.jl).
+Importantly, for an immutable type, the mutation actually involve the creation
+of a new instance with [Accessors.jl](https://github.com/JuliaObjects/Accessors.jl).
 
 
 ## Contributing