My question was simply for future informational purposes - I do that I knew my tires were not appropriate for the conditions I found myself in Saturday - and I had not planned to ride in deep gravel of course.

I really was rather impressed with how my LHT felt in those conditions. I was also quite impressed at how it did on a couple of very steep hills once I returned to the pavement - it was nice to not spin on the little chain but even on my easiest gear I was able to dig in a little. My bike felt much better than it ever has in the granny gear - probably because that was the first time it was appropriate to BE in that gear