This thread is what finally inspired me to join instead of lurking.
The French Canyon is one of my favorite places to visit, and the Royce Falls are worth a visit from anywhere within range of a reasonable dayhike.
There is a Rock, right in the middle of a Grassy spot, at the base of the falls.
It does take some steep scrambling to get to this part, but not too difficult. The chair is the perfect shape to use as a "Lazy-boy" chair.
I could happily spend hours just sitting on the "chair", spray from the falls all around me, and looking out over one of the great vistas of the sierras.