Okay, so I did a lot of testing of different b/o's for double rib and...
The one that won (for me) was Stanley's decrease b/o "in pattern," (switching from knit to purl to match the rib). Not a perfect match, but very easy to do, and not bad looking. A definite improvement over basic chain b/o in pattern. (Note: There seems to be a version of chain b/o that is sometimes referred to as decrease b/o, but I'm specifically referring to the decrease b/o found in the Stanley book.)
I found a few different ways to do tubular (aka kitchener, aka invisible) for double rib, and I didn't find any of them particularly nice looking. I tried a version on the needles (tricky), a version off the needles (a bit easier), and another version that involved "exchanging" stitches to make the double rib into the single rib before doing regular tubular b/o for single rib. They all required two rounds of double knitting before the final b/o, as well as use of a tapestry needle on the final round.* I decided it was not worth the effort given that the decrease b/o looked better, and was about 10,000 times faster and easier.
I'm sure that nobody's going to be examining the cuffs of DH's new socks, but it was a fun exercise anyway. YMMV, of course.
*It was a total AHA! moment for me when I realized that tubular b/o was called tubular because the double knitting creates a little tube. Why it took me so long to realize it is beyond me.
When you did the kitchener for single rib, did you do 2 rounds of double knitting first? It doesn't seem to be a requirement (Amy doesn't show it in her video, and I don't think the Vogue book mentions it either), but at least 3 books I found recommend it. It may make a difference in stretchiness.