The techniques taught for ground exams have little or no relevance to how one actually operates an aeroplane in practice. Do the exams as they are taught and remember each licence and rating award just opens the door to learning how to do it properly!
I no longer possess a whizz wheel and can't remember how to use one and while I have several gadgets that would do E6B I've never used it.
Curiously enough I can still plan and execute both VFR and IFR flights because I use software tools and GPS!