I just spent quite some time to find a bug in my code.
In my .tml I use a <t:BeanEditForm>. As soon as I added
private Form form;
to the corresponding .java file (need to do some validation), the form was no longer rendered (the rest of the page was there, only the form was missing). Of course, using
private BeanEditForm form;
instead fixes the problem.
It took me long to find the problem, because there was no hint of what I was doing wrong. Maybe Tapestry could be enhanced to generate some kind of error message or warning in case of such misaligned component classes, instead of quietly dropping the form.
Of course, enhancing the system to be able to use Form instead of BeanEditForm if you need just the basic features of Form, and not BeanEditForm in your java code, would be even better, but this seems difficult, as Form is not a super-class of BeanEditForm.