Funny you should say that Neil, Having spent a good few years training the military youngsters it became apparent quite early on that the majority of them left school with the bare minimum of qualifications, and many of those suffered from an SPLD, Dyslexia, Dyscalculia and ADHD to name a few.
Many of these difficulties were not initially picked up at school leaving the learner at a disadvantage from their classmates.
It was also noticed that the majority of these youngsters were kinaesthetic learners i.e no amount of theoretical training would get the point across, but get them to actually do the job a whole new world opened up to them.
While the majority turned into some seriously good engineers, some were just not cut out for it. There has to be a passion for the types of jobs we were asking them to do, and sometimes it just didn't happen. Not every son follows the passions of his father, and quite frankly, in order to preserve some degree of versatility, they should not necessarily be encouraged to do so, but developed in areas that they may show a 'passion' for.
I must admit that after a long career in aeronautical and marine engineering I was a little disappointed that my own son did not want to follow a similar career, but he decided to go the electronics and networking route and he freely admits that he has no interest in metal whittling but he's damned useful to have about when the miller motor decides to throw a fit, or the air con packs up.
Each to his own, and as parents we need to encourage the development in whatever route our offspring decide to take, and not to give out negative feedback just because we feel we have to.