One last thing to note:
In any case, since we can't actually deploy our JSP-based JNLP
files to our project site, why don't we just keep index.jsp and
index.html separate. index.jsp can be used to launch Web Start
versions, and index.html can be used to launch the applets.
OK, but attention: index.html has priority over index.jsp so at least
we have to copy inside war only the one that interests, and the same
also for our site (to avoid confusion, also if jsp there isn't
allowed).
Why don't we just rename index.jsp to web_start.jsp (or
web_start.html, since you are now using JavaScript instead of JSP)?
