Why can my instance initializer block reference a field before it is declared?

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From docs:

The Java compiler copies initializer blocks into every constructor.
Therefore, this approach can be used to share a block of code between
multiple constructors.

The above statement is slightly misleading, because if we follow the explanation of the above doc we can rewrite the original code like this:

public class WrongVersionOfWhyIsThisOk {

    int a = 10;

    public WhyIsThisOk (){
        a = 5;
    }

    public static void main(String[] args){
        WrongVersionOfWhyIsThisOk why = new WrongVersionOfWhyIsThisOk ();
        System.out.println(why.a);
    }
}

But running WrongVersionOfWhyIsThisOk will produce 5 instead of 10 that original code produces.

But in reality it is both the initializer block and variable assignment are copied into constructor:

public class RightVersionOfWhyIsThisOk {

    int a;

    public RightVersionOfWhyIsThisOk (){
        a = 5;
        a = 10;
    }

    public static void main(String[] args){
        RightVersionOfWhyIsThisOk why = new RightVersionOfWhyIsThisOk ();
        System.out.println(why.a);
    }
}

Update:

Here is the doc describing in detail the initialization order and constructor invocation:

4) Execute the instance initializers and instance variable
initializers for this class, assigning the values of instance variable
initializers to the corresponding instance variables, in the
left-to-right order in which they appear textually in the source code
for the class. If execution of any of these initializers results in an
exception, then no further initializers are processed and this
procedure completes abruptly with that same exception. Otherwise,
continue with step 5.

5) Execute the rest of the body of this constructor. If that execution
completes abruptly, then this procedure completes abruptly for the
same reason. Otherwise, this procedure completes normally.

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