Indeed, I see a big difference between developers in my team based on their general reasoning and discrete math skills. How capable are they of abstractly inter

Indeed, I see a big difference between developers in my team based on their general reasoning and discrete math skills. How capable are they of abstractly interpreting code in their head? Are they used to thinking about how to prove something is correct? Are they used to thinking in terms of graphs? That sort of thing. Those are technical skills that seem pretty difficult to learn.