Prefer error over silent skip?

[vreuter]

When passing an invalid option, it seems preferable to run nothing and display an error message, rather than silently executing and ignoring bad option(s).
Example: -exapnded instead of expanded passed to aggregate runs the program with no additional stats calculation.
Not a big deal for quick runs, but it could be a bummer to really need those stats and submit something long-running, only to find the output lacking in those additional fields and need to rerun.