Good point... so, do you mind having a look at [this Gist](https://gist.github.com/fazy/5568416)? 

It seems to behave as expected, that is to say it reproduces the bug and gives me this output:

    updated value
    updated child value

although the real expected output is:

    updated value
    initial child value

If I haven't done anything obviously wrong, I'll file a bug on the JCR Jira.