In the codex it says:
If you use postname as the only element in your permalinks to create a structure such as myblog.com/post-title, the rewrite rules may make it impossible to access pages such as your stylesheet (which has a similar format) or the /wp-admin/ folder. It’s best to include some numeric data (e.g. the post ID or date) in the permalink to prevent this from happening.
What about using the category name and the post name without a date? Will this cause the same problems?
Thanks so much.