Ubuntu :: Mounting A Partition On A Partition Unstable?

I have come across the following statement: " When a FAT32 partition is mounted at '/media/windows', all access to '/media/windows' and everything below it is transparently handled by the Linux kernel using the 'vfat' module. Applications need not know they're dealing with anything else. However, mounting a partition at a location inside of another mounted partition is unpredictable, unstable, and generally a bad idea. "

Is it correct? Most of my partitions are mounted on /home, which is on a separate partition; and I have one "level 3" partition. I have been using Ubuntu for nearly three years so far with no problems (except for /home losing it's format once).