There is a bug in the way the template handler processes the end of a template, but it is not gonna get fixed soon, so heads up!
{{Template_Name|field1|field2|field3=whatever}}
will work just fine, but...
{{Template_Name
|field1
|field2
|field3=whatever
}}
will not. It will include the linebreak on the end of field3!!! The fix for this is simple...
{{Template_Name
|field1
|field2
|field3=whatever
|}}
Ending the template call with |}} prevents the problem.
As I see them, and I AM looking, all Usage diagrams will have the |}} on the end so that cut-n-pastas will have it, but if you see a call that is NOT working, make sure it has |}} on the end before calling me!