2023 update: these days I call this a Double Slip Decrease, or DSD, because other lace designers use that name.
In some circumstances, I like to use a right-leaning double decrease that is not k3tog. That is, it’s a mirror of sl1, k2tog, psso. I do this: slip 1 knitwise, slip 1 knitwise, slip the 2 together back to the left needle so they switch places, and then I knit 3 together. It doesn’t look the same as k3tog; it lies flatter and suits certain designs better. I haven’t found it any of the knitting resources I use, but I am certain I can’t be the only knitter in the world who uses it.
The question is: have any of you encountered it, and do you know of an abbreviation for it? I’d like to stick with standard terminology if at all possible.