Imagine a tool that made horses run faster. Maybe something that when you flick a switch on the saddle it activates something that compresses the horse's nuts. A very useful invention for jockeys.
If someone comes along wanting to adapt that invention to cars you should hesitate. Not because the device could not be adapted to cars but because the person is adapting a tool rather than developing one.
This is actually fairly entertaining.
So, to carry the idea into practical terms, you are saying that engineers who use calculus to solve
problems shouldn't be trusted because they haven't created their owns mathematical tools for solving
engineering problems, right?