I have enabled the option ‘show system files’ so that I can see system forcers and files.
For example now I can say /usr folder although it is greyed out.
The problem is that double clicking is not working in these system folders so that you can access them.
Yes, you are right. I have just tested it here with basic Finder under 10.9.3 system.
A workaround could be to use the keyboard shortcut for entering a folder CMD+DOWN_ARROW. I’m sorry I’m not going to fix it at this point.