Actually that happened during a 4 hour enduro in 2007. It failed about 45 minutes in. We drove for the next 3+ hours on 35-40 minute stints (all we could handle) until the event was over. Finished 5th.

Replaced the pump and rack after that event and haven't had any issues since. I do keep an extra pump and rack with me at the track as a spare.

The steering effort goes thru the roof and slip angles are just guesses on what you actually need to get thru the next corner.