Help with Robert Lang cockroach step 68

[BradBlankenship]

I am confused with step 68 of Robert langs cockroach. It says bring layer a in front of flap b but I can't wrap my head around how to do this. I may be missing something simple but need help please

[dinogami]

Basically, you have to unsink a single layer of paper. The step is the equivalent of swinging the whole top assembly (B) to the right, then closed-sinking it to the left underneath a layer of A.

Personally, I dislike the "wrap a layer" method of depicting/describing such de facto closed sinks. Sure, it's an accurate description of what's going on, and it saves a diagramming step, but it generally seems to cause more confusion among folders (at least, until they figure it out)--I remember it took me quite a while to decipher what it meant the first time I encountered it (long before this forum ever existed, I think)!

[jupstin]

Thanks so much for this. I was stuck here, and a google search led me straight to this page.