AppleScript's "try" command gives up too easily.

Question

I want to do some conditional branching using "try." For the record, there is no user on my computer named "Batman." I want the script to continue even if it doesn't find a user this time.
Here's my code, in Snow Leopard 10.6.8:
try
          do shell script "dscl . -read /Users/Batman"
on error 56 -- which reads "error "<dscl_cmd> DS Error: -14136 (eDSRecordNotFound)" number 56"
--keep going; "Batman" is only one of a number of user names I am testing!
end try
The script fails and exits with a message that reads:
AppleScript Error
<dscl_cmd> DS Error: -14136 (eDSRecordNotFound)
I thought the whole point of "try" was that it would allow your script to continue running even if it ran into an error...? 

Answer 1

This isn't the code I need to run. I am testing a list of usernames to see if the accounts exist on our Active Directory domain. I used this code because it fails to work just as well as the real code, and I don't want to limit my pool of genius lifesavers only to people who are bound to Active Directory.