Nice video Clint. Yes the North fork is steep but I find the footing much better than the South fork and it is in the shade. The South fork is covered with baby head rocks that, to me, are easy to slide or roll on. I would much rather go down the north and up the south like you did. Not surprised that the ranger did not know about Split rock, if they had ever read anything or walked the trail they would know about it.
A great return route is to take the alternate fork at the top before the big climb down and drop into Ernst Valley to the Strawhouse trail and follow it back out and through a cool little canyon before it reconnects with the Marufo Vega trail. It only adds a few tenths of a mile to the trip.
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