Can I just tell you how much I hate those Ishihara tests? I don't see shit in that OP one (which was exactly what I expected).
Once upon a time, Panasonic did a print ad for one of their new color printers that was a dot test that read "Panasonic", with nothing else on the page. Not super-effective advertising - although I suppose color-blind folks weren't necessarily the target demographic...
Yes, they do.
I kinda hate them because non-colorblind people generally say one of a few things when conversations about them come up: "OMG do you really not see any numbers on there? It's so OBVIOUS", "Wow... so what color is this [insert random obvious thing]?", or "So you're colorblind? How do you deal with traffic lights? LOL".