You're very close! The OS will try to load the files individually, but the file system knows that the symlinks all point to the same location so it will use a cached copy generally. You should get the same reduced disk activity that you do running from 1 physical directory, but you can keep your settings, macros, addons, etc. separate.

I don't think that the disk configuration will have much effect on CPU activity no matter how you do it. That's my theory anyway. You can check using perfmon.