I hate to say it, but you are most definately a Weasel.

In my time as a DBA, I learned that if I wanted to keep my databases clean and running well, I had to keep a good relationship with the development teams. Often that lead to a lot of dumb questions, but sometimes I got the opportunity to make the database better and teach the developers a few things about how you should be programming with a database.

Now, in this case, I would have asked a few more probing questions, like "Is a value of ' ' invalid everywhere?" or "Have you tried rtrim()?" I would have also checked the original specifications for the control files or the input data files.

What you did will keep the developers from coming to you when they have questions, and more importantly, design questions. Now, in six months when you have to look into why new tables in your system are blowing out extents or help developers with why queries are so slow in your production databases, you can look at this episode here for the reason why.