The route is in great shape. In fact, there's a path almost all the way to the final climb to the South Sister. I remember this route in the nineties. There was hardly any path. The old route would backtrack off of the South Sister. The new route (founded by Ed Forkos - I think) continues north on the ridge of the South Sister to an easy class 3 down climb. It then meets up with the standard route.
It was always tricky to find the final down climb off of the South Sister. Now it's very well cairned and easy to find. The route over to the North Sister is easy to follow via a path and cairns. This is one of the best hikes in Mt. Charleston in my opinion.
Here's video of Tre-c receiving her plaque: