Yep, I’ve used it and found it very realistic. But a word of warning…a little goes a very long way. As Emeril is fond of saying, you can always add, but you can’t take away!
True India Ink is black. Unfortunately there is some stuff out there sold as Inida Ink that has a way of turning blue, and weathering is when you tend to notice this most.
For road weathering I have used charcoal sticks (an art supply) feathered with a soft brush.
I’ve used India ink and found it very messy. I prefer dilluted black craft paints. I mix it with distilled water, and add a bit or alcohol to make it stick better to surfaces.