I agree, there is usually a point along the way that stumps you so bad that it´s distracting you from just moving on, it´s not necessary (probably) but it´s a good way to scratch that itch. I could also see a point where it´s just not needed, looks like you may have got there once or twice already, I can´t see how it would help beyond a certain point, if your goal is general functionality (whatever that is) in the language.