It's not you hyperactive. These directions will not make the stitch pictured. I've tried it flat, in the round, wyb, wyf, purling, knitting. Nothing works. I was interested in this pattern too, and the instructions for the lateral braid were so clear, but this is not working. I hope you get an answer from the designer.
When I searched for "linen ridge stitch" I can't find anything that looks like this either, but I didn't do an extensive search. I looked at Knitting Fool, and through all my Harmony Guides and one other and found nothing. Very interesting.
I am not too dumb, I am no knitting-fool!
I was really doubting myself.
I did try it flat, wth purling,
flat with knitting those rows
in the round with purling and knitting
(strange, because the pattern says "row" but the thingies are done in the round... so all was possible.
slipping the stitches purlwise (as it says) or knitwise...
wyif wyib and so on.
My husband was looking half amused, half worried.
I did find the designer's web blog, though. So I will try to get clarification from her.
She did write that this was her first pattern making. Maybe something was just from memory and wrong?
I will try tonight if it works when you purl through the back loop...
My google and pattern listing search was no better than yours, either.
But an email might clarify it all. I will let you know!