Ok, so, on the off-chance I don't have quite enough on my to-do wish list, I really, really like the look of Or Nue, and I really want to learn how to do it. Alas, chances of it being accurate to either R or my periods are pretty much nil. I do need to find any references to pre-300 BCE embroidery, but, alas, they're fairly scant so far. It really does look like it was mostly woven-in decoration, or printed on, probably with block prints.
However, I found some ideas for cheating. One is the Turkish variation of double running stitch that I saw at Festival - it's essentially just worked as a background, usually offset slightly, so it looks like a twill weave. If I can be bothered, I might come back and put a picture here.
Second is pattern darning, as is described by How To History, with an awesome video tutorial.
But back to the pretty shiny goldwork.
There's a nice, short article by a fellow SCAdian on the matter, which recommends strongly only using one strand of silk as the couching thread.
This article is in an annoying format, but suggests that any goldwork project be worked on two layers of fabric - an upper of silk or similar, and a bottom one to reinforce it. I presume, however, that linen canvas will be sturdy enough by itself, but I should double-check.
Mary Corbet links to this article: while she hasn't yet gone into Or Nue, she does have awesome tutorials on couching goldwork, which this is just a variant of. While the linked article has some very pretty pictures, it's a bit useless for the how-to bit.
On a side note, if my fairy godmother is out there, I've been very good and I'd like this for whichever holiday you feel like celebrating.
The local Worshipful Company of Broiders recommends getting silk thread from here, and goldwork supplies from here. However, I'd take this with a grain of salt as their webpage is so out of date - I'm more tempted to just get my thread from wherever Mary says is good, because she, obviously, is the Goddess of Needlework.
Oh, and to finish off my brain-dump, here's an idea for this year's generic Mandatory Fun Happy Gift-giving Season present:
Otherwise, blackwork bookmarks might be the way to go for Mother's Day.