I may be wrong, but I think the BO at the beginning of the two rows makes it so the slant of the BO is symmetrical on both sides. That is, the BO are both pointing toward the center of the work.
ALSO, think of this:
ROW 1: BO 23, K 37 BO 23.
ROW 2: ???
In order to turn, you would have to BREAK the yarn.
The pattern is written:
ROW 1: BO 23, K to end.
ROW 2: BO 23, place remaining stitches on holder.
When you end, your working yarn will be with those stitches you placed on the holder. Will you have to pick up stitches later to add a collar or hood? Would you have to seam together the collar or hood that you've knitted separately? If so, leave enough yarn from your BO so you don't have to join yarns when you seam it.
I don't know if this answers your question, but it might be why the pattern was written that way?