I walk the south end every morning and use many of the tunnels. I choose to walk against traffic, hugging the side wall as close as possible. Given the curved roof line of the tunnels, carts tend to ride closer to the center than the sides. I do walk as fast as possible when I'm in a tunnel, though...
I've not had an incident thus far with that strategy. That being said, I kinda like the idea of wearing a flasher.
BTW, I see the light fixtures, but have yet to see them illuminated.
What *does* surprise me is the number of path walkers that walk *with* traffic. I see several every day. Seems like a death wish, especially if they have their earbuds in or their dogs on a long-ish leash!