I don't know how os x works. Once you've browsed to a certain share, even after hiding it, it may still know it's there, and attempt to connect to it anyway.
I know the option 'browsable to network clients' works when unchecked. I have a share of the root pool with that unchecked, so that it's not visible on the network. Normally I access shares of datasets, but sometimes it's easier to access the root pool. Since the share is not visible, nobody but me knows it's there.
Like cyberjock says, make sure you restart cifs after making changes, just to be sure.