It's absolutely infuriating that you can, with a simple NFS, cause an unkillable, unremovable, always there process to exist. There is simply no reason to require this.
For non vital filesystems, I use "-o intr,soft,timeo=5" at NFS mount time. This causes syscalls to return EINTR and timeout without hard locking. It can sometimes confuse userspace, but at least you don't get a stuck process.
I always preferred "intr,hard", because having filesystem operations fail really stresses out a lot of userspace applications. Most developers haven't thoroughly tested their handling of "what if this disk operation fails?", because it's a pain to do and a rare case.
