I don't keep my funds on any exchange if I do so, it's very minimal and not that much of amount that I can't avail to lose. I have read somewhere this strategy of hiding your files and folders, although it's not that of a security but it's another way to simply add and keep your important files that contains your keys (if you are keeping it on a file format).

A backup is a must so don't depend mostly on your single file that keeps your PKs or the written format that you make. Always create a backup or duplicate or even more where you can keep it in a very safe storage that can't be find out by others.