assuming the permissions are known as soon as the page is rendered and not determined by an asynchronous call, then you can go safely with adding the class names.
In addition, if the data is asynchronous, you could add the said class names during the databound event.
Regardless of the scenario, as long as the permissions data is available at any point in time, you could apply the styling from that moment onward, be it on page render, grid databount etc.
We would go into more details, but thus far we have noting concrete to cling to. If you could prepare a sample project and attach it to this thread, we could evaluate it and write back.
Just a minor note, this here is a forum thread and you are limited to the types of attachments you add. If you want, we could convert the forum thread to support thread, or if you prefer, you could start a new support thread.