If you know what you are doing it is not difficult, but if you are doing it for the first time it a good tool to learn how to think about all the repercussions

If you know what you are doing it is not difficult, but if you are doing it for the first time it a good tool to learn how to think about all the repercussions of how you program something. MISRA isn't really to catch problems with c it is to catch problems with people using c. So knowing what those problems are and how to avoid them is incredibly useful.