Recently I was perusing Atwater's The Shuttle-Craft book of Handweaving (Sixth Printing 1966). On page 177 it reads "No. 99 is a similar figure to the above, but much smaller and arranged on opposites. Woven as drawn in with the accidentals omitted. " What are accidentals?
Accidentals are the short weft-floats that occur at the junction of two overshot blocks on opposites.
ie 121212343434...you have a 12 A block and a 34 C block but where they join you have a 23 which is a B
She was saying to treadle it tromp as writ but not the accidental...so you wouldn't use the 23 treadle. I hope that makes sense. It makes it look more like Monk's Belt.