Riding against traffic on the sidewalk means the driver at the t-stop is looking left at traffic, not right at you.
Coincidentally, the shortest route back to my house involves using the sidewalk, but against traffic. There's a t-stop along this sidewalk and all the motorists getting off the freeway pull up to it, look to their left and if no cars are coming, they gun their engines and make the right on red. This t-stop is the very reason why I won't go home this way. I actually ride about 3 miles out of my way to avoid it because it's so dangerous.