@mwichary Interesting. I didn’t pick up on the “breathing” aspect but I recall that the slow pulsing was quite soothing. It was also useful and usable: it conveyed information if you looked at it, without attracting attention to itself.
By contrast, many things (like cursors) blink too fast for my taste, saying “Hurry up and type something!” Even a non-blinking red LED, like on a TV in a darkened hotel room, is too harsh. I carry a roll of gaffer tape in my travel kit for such situations.