You shouldn't have to reboot the server to test failover. If the failover doesn't work, the server is likely to reboot itself, anyway.
As for "exercising" the multipath, I'd do what you did: pull a fibre cable, shut off the FC switch, and reboot the SP. Simulating a card failure isn't really exact, but you could try unloading the driver for a slot.
You also might look at your SAN vendor's multipath support. I doubt that I'd trust Novell's built-in support. We use Powerpath here.