Those should come in handy while working upon things. There is also the Scrambling tab in the Settings\Document Properties of the app that contains the sensitive data where you can scramble the values, but that is going to do so for everyone, so if some folks need to see it, that will not work. The OMIT system field in Section Access should be the way to go per Marcus' comments.
Be sure to give Marcus credit as well by using the Accept as Solution button on his post(s) that helped, you can mark more than one response as the solution if multiple ones did help.
To help users find verified answers, please do not forget to use the "Accept as Solution" button on any post(s) that helped you resolve your problem or question. I now work a compressed schedule, Tuesday, Wednesday and Thursday, so those will be the days I will reply to any follow-up posts.