In my experience reviewing engineering calculations, I end up doing a lot of work either by hand or in something that recognizes scientific/engineering units li

In my experience reviewing engineering calculations, I end up doing a lot of work either by hand or in something that recognizes scientific/engineering units like MathCad or SMath and that also displays the equations. I have marked up 100+ page reports, checking every number, in red pen and doing the math on a handheld calculator, checking the page references for all referred equations. The best habit I had, from reviewing others' work, is to give my own work the same treatment. This is the only way I got a long engineering report out in a reasonable amount of time: by catching my own mistakes by actually printing it out and going through it with a fine tooth comb. It takes time, but not as long as you would think in many cases. I've seen others just kind of skim a document and read a few words and see the shape of the equations, then sign off on it for non safety parts. Even then, you can easily lose lots of money on simple mistakes. I've also seen inherited spreadsheets that went through several hands, with magical things added, that the past two people using it never checked. Some people never learn to really go through and check.