I gave this one a though, its really not much superior to current impl but I still prefer your suggestion (as its few lines of code less upon update). As you have noticed, I am now using the XML description builder, so there is no longer need to specifically handle the writer. Just create XML description once and writers and readers are created effortlessly. 

Nevertheless, I have reworked it, so now only thing that needs to be done in the writer upon update is to extend the new version of the reader class as to inherit the xml description. 

Thanks!