That will work “even more most of the time”, failing badly only if you get asked to fly via “airway YYY”, but that is very rare;
My GNS430 does not know airways and given that I fly by programming the GNS, I do not fly airways. I will ask ATC for waypoints, they know them by heart anyway. Whether that is unprofessional or not, I don’t care. Don’t remember the last time I was given an airway designator.
when one has to replan the route and doesn’t have a printer or some means of displaying the new route, or one can print it to a PDF but it is too much bother to load the PDF to the tablet in use (most likely to be the case with an Ipad given the very limited ways of getting data into it while travelling).
Never had that problem, there’s 3G all around the world and certainly everywhere I takeoff with my airplane. I don’t print anything. Even in Africa all I had was PDFs on my tablet and phone (backup) and that included spontaneous replanning due to unforeseen difficulties.
