I'm not sure that I agree with what he has to say, "The most important reason is that ULS does not do much to secure the data in your tables, which is what most people are really looking for. Anybody who knows databases can connect to your tables using another database and modify your information. So Access ULS is almost meaningless when it comes to actually SECURING your data."

What I have found is that if you implement the security correctly and remove all the privledges from the Admin user and the Users group then they can only access the data by going through the security file even from another database.  However, if you leave read priledges on the Users group then they can modify your data from another database.  That in combination with stopping the F11 key and the shift enter access to the database does allow you to block access to your data.

With that said, there are a lot of programs that you can down load on the internet to break into the security.  So I agree that it is not very secure.