Yes, that would be helpful - thanks for the suggestion.
The problem is that the "Send message" page at bitcointalk is not linked to the actual username but to a user number.
E.g. your's looks like this: https://bitcointalk.org/index.php?action=pm;sa=send;u=167171
So when creating a new order users would have to enter their user id number as well.
I might make this an optional field in the form.