What you say is true - but the idea is not to use this in production code. It's just a means of testing some fundamental C++ concepts which I outlined in the post.
Kindof - if you're a startup and hiring for a position that requires knowledge of java, then IMHO it's a fair question. Most startups don't have the resources to train employees for 6 months.
But yes - the testing material in most certifications is not a good indicator of problem solving abilities and I wouldn't make any hiring decision based on them.
In my experience, pure mathematical knowledge just by itself seldom translates into good coding skills. This is after I've TAed Maths, CS and Physics courses for almost 4 years.
Typically we have 45 minutes to interview someone and asking a question where one has to derive a mathematical formula using induction/ calculus is not well served to gauge their programming abilities.
But I totally agree with you on your last point - just because someone is not a good hire now, does not mean they never will be - that's why even if you don't crack an interview, you can reapply in 6 months time.
Yes - it's mostly applicable when you're creating APIs and developer solutions. But even in case of internal tools/ exes, you might need to share functionality with a internal partner team and it's helpful if they don't have to read code they don't need to use.
Good points ! I ran into some difficulty translating the boost::shared_ptrs to C++ 11 standard shared_ptrs a while back while adopting some open source tech for xbox.
Also you're spot on about people touting the smart pointers as a silver bullet for all memory issues leading to an overuse of these otherwise fantastic tools.