I was looking at a Vladimir Teroikhin pattern in Fall 2006 Vogue Knitting and noticed a "fully fashioned" pair of decreases I'd never seen before. He abbreviates them as 6-st CL-dec 2 and 6-st CR-dec 2 -- not sure how you'd pronounce them: "6-stitch Cable Left/Right-decrease of 2 stitches", perhaps?
Here's how it's done.
Left: Sl 2 sts to cn and hold to front, k2, then [k1 st from cn at front tog with 1 st on LH needle] twice.
Right: Sl 4 sts to cn and hold to back, then [k1 st from LH neele tog with1 st from cn at back] twice, k2 from cn.
He left a selvedge of 2 sts, using left-decr at left edge of v-neck, right-decr at right edge.

I tried these out and found them very cable-y, if you know what I mean; not invisible by any means. But then he was using them alongside a very pronounced (30 st!) cable at the neck-edge. I would say they would be too much in any but fine-weight yarn.
Look alot like decreases I see in store-bought sweaters, but more pronounced. I think those boughten-sweater decreases are more likely done by slipping just 2 sts to cn, and holding to front for right-decr and to back for left-decr, and then working the sts together like in this Vogue pattern. My guess is they do this (double decreasing) so that they don't have to do the decr as often.
Don't know how frequently I'd want to use this, but I'm pleased to have now made sense of what I've been seeing in store-bought sweater shoulders.

Most store bought sweaters have been machine knit (or machine-loomed), and fully fashioned decreases done on a machine, although hand manipulated, produce the type of decreases you refer to in ready to wear. You can duplicate that look by using the wrong decrease--that is, if an ssk is specified, use a k 2 tog; and vice versa. Sounds like the one you describe is used to emphasize it even more.

It's not so much the direction of the decreases, as that they use a cable needle. I've never read a direction like that.
And they make double and even triple decreases that way.

Before this, the KSP (or KRPS or KSPS) was the most exotic I'd seen.

Hmm, that sounds interesting. I'll have to try it.
Thanks for posting the instructions!

- Lesley, becoming more inspired as I read what people share with us.

Thank God for you ... I'm knitting this Teroikhin pattern for my sister and have been struggling with the directions for this decrease ... you are my Christmas angel!!!!