I once was "admonished" by a fellow student for suggesting that to fly from LHR to Truro we should head westish, with "No no, we have to be a little more accurate than that, we should steer 087deg magnetic" as he was playing with his new electronic thingy.
The point I am trying to make is that to learn the basics & do most of it in your head is extremely usefull. Errors can be made on any piece of kit. The square protractor can be rotated 90deg & that set of numbers written down, I've seen it done, & nearly done it myself.
The triangle could be drawn out on the chart with a Nm calibrated rule, just to demonstrate its function. Knowing the basics like reasonably correct direction of track by ref to the chart & being able to point at the target destination, even very roughly, should eliminate gross errors like heading off on a reciprocal. Reliance on anything other than a chart & compass can/will produce an error at some point. Being able to use the CRP1 I think is not a bad thing, to learn the intricacies of setting up a GPS requires the teachings from a 10yr old Nintendo pilot. But when my daughter kept asking "what has time got to do with it?" while I was muttering about deg-mins & seconds, makes me wonder if the 10yr old would be much use. Old fart I may be but I do believe that knowledge don't weigh nothin, & the batteries don't go flat.