Yeap, pipelining for HTTPS connections, but I suspect it is not supported in Firefox 2 and possibly even Firefox 3. Note, I am currently running Minefield 3.1a1pre trunk, which is the precursor to Firefox 3.1 branch.
The redirection limit is more of a security issue than a performance tweak. 10 is an acceptable value. 5 would probably even work for most users.