JSP 2.x - Tag files with body-content="JSP"

Question

I've been looking at the JSP 2.1 draft and see that, as with the previous JSP release, it is not allowed for tag-files to have body-content="JSP". I've tried to find a good answer for that on the web, but there's no one who can enlighten me. I've tried to tweak the source of Apache Tomcat 6.0.13 (Validator.ValidateVisitor and TagFileProcessor.TagFileDirectiveVisitor, both in org.apache.jasper.compiler) to accept body-content="JSP" in tag files - with great success. It is possible to have scriptlets within tags from tag files and it works as expected.
My reason for wanting scriptlets in the body-content of tags from tag files is that it would encourage a more contextual, nested (and in my eyes, a more beautiful) structure of JSP-pages, as opposed to the JSTL flat structure, where f.ex. the sql:query tag does not reside within a sql:setDataSource tag, but instead refers to the datasource through an EL-variable. I suppose that it has been constructed in this way only to make it possible for programmers to include scriptlets in-between sql:query tags that use the same datasource.
Not that it is not possible to nest tag-file tags, but I suspect that many programmers then would like to keep a flat structure so as to maintain the possibility of inserting scriptlets where needed - outside any tag which is based on a tag-file.
So, why is it not allowed for tag-files to have body-content="JSP"?

Answer 1

Thanks for the reply, evnafets.
I'm aware that scriptet-code is generally being discouraged, although I don't understand why. I think that having a standard tag-library is a wonderful idea, but in the case of JSTL, I'm not that pleased. It relies heavily on EL, which I see as an unnecessary abstraction.
Let me give you an example. The JSTL does database-connections and queries in this way:
<sql:setDataSource var="datasource" url="jdbc:oracle:thin:@localhost:1521:TEMP" driver="oracle.jdbc.OracleDriver" user="scott" password="tiger" />
<sql:query sql="SELECT * FROM EMP" dataSource="datasource" var="resultset" />This could also be accomplished without EL in a hierarchical structure:
<sql:dataSource url="jdbc:oracle:thin:@localhost:1521:TEMP" driver="oracle.jdbc.OracleDriver" user="scott" password="tiger">
  <sql:query sql="SELECT * FROM EMP">
    BodyContent <% perhapsWithScriptlets; %>
  </sql:query>
</sql:dataSource>...using TagSupport.findAncestorWithClass for the query to reference the datasource which it is enclosed in. (in Tomcat, the class would be called dataSource_tag. BTW, why is this not standardised in JSP?)
I would then also like to be able to use scriptlet-code inside the tags as I could if the tags were written as tag-classes, extending BodyTagSupport, and being defined in a formal, cumbersome TLD file.
Why the difference in functionality between SimpleTagSupport and BodyTagSupport - or rather; why is it then not possible to specify that a tag-file should extend BodyTagSupport rather than SimpleTagSupport?