what's the deal with "user error" on fail?

[David Roundy]

When one triggers an exception with something like

fail "Error opening file"

The user gets a message like

Fail: user error
Reason: Error opening file

which is confusing to the user, because it the user's fault.  Is there some
other way that it is recommended one fail? Or should I be catching
userErrors at the top level and failing with my own error message?
-- 
David Roundy
http://www.abridgegame.org/darcs