No need to fear! Use --dry-run to confirm your command line before making the changes. It's documented in that very man page!

I have a list of aliases I pass to my minions, one is to alias rsync with this, and the real rsync is aliased as rsyncplz

That kind of stuff sounds good, but it’s dangerous. You risk getting used to it, and then getting hosed when you’re on a normal system. Some people use a similar thing where they set "rm" as an alias to "rm -i", i.e. ask interactively before removal of each file.

I once heard a story about some SunOS consultant who was used to "rm" being an alias for "rm -i", and the first thing this consultant did, as root, was to "cd /etc" and then "rm *".

One of my first introductions to the fact that GNU getopt is much different from BSD/UNIX getopt was running `rm * -i` on Solaris. Instead of prompting me for which files to delete, it removed all of my files and then printed an error about failing to remove the non existent file "-i".

In principle this could be solved by having two aliases `rsync-dry-run` and `rsync-for-real`, and aliasing `rsync` to `echo "Use rsync-dry-run or rsync-for-real“`.

That's great, I'll do that now. Thanks!