I have no idea!
Have you tried writing Mary?
Or, go here, read the bottom paragraph and plead for help - she does say to write her: http://hipknitism.com/classes/basic_.../lesson4.shtml
My guess: K enc: sl 1 st from L to R, using the R needle lift the next st on the L needle from the back - now you have 2 slipped, unworked sts on the R needle - knit these thru the back (?).
P enc: sl 1 st from L to R, using the R needle lift the next st on the L needle from the back - again you have 2 slipped sts - purl both.
I'd have to try this, but it sounds doable.