I can't help much with those questions - your line about "rote learnt knowledge with no true understanding" pretty much sums me up (except that I don't have much of the "rote learnt knowledge" :-)
I *do* hope the basic construct being demonstrated in that cookbook example is not doing anything too dastardly, as it's one that I've been using extensively, and for quite a long time (in, eg, all of my Math::* modules). I've found it to be very serviceable and reliable - which hopefully stands it in good stead.