I think Phil is refrering the old version of the TLD specification. As per the JSP 2.0, there is no jspversion element in the tld. For the JSP 2.0, there is no XML DD document, the scema is definded using XSD. The <body-content> is mandatary as per JSP 2.0 for <tag>.
In case of a distributable application each JVM has their own instance of ServletContext and ServletContext is not shared across applications and there is only one default context in distributed environment have you refered to the default context as a load balancing server (physical or virtual)
So in short
1.The <body-content> is not mandatory
2. Its default value is JSP
3.But for simple tag its scriptless
For classic tag's, the default value is "JSP".