As I expected, the construction required patience and logic. Every piece is basically a square or rectangle and there isn't a lot of form-fit in the final product.
You then stitch the shoulder pieces to the fronts and backs, lining them up with the outer (shoulder) edges to create a kind of strap on either side, joining the front and the back.
You construct each sleeve using a square of fabric as a gusset and an additional long thin strip of fabric that gives room for movement. The sleeve is then joined to the shoulder strap and the sides of the front and back panels. There are a lot of long straight seams, traditionally joined by encased flat seams. I followed tradition and used this method. My mother was partial to using this method for seams. Perhaps it is very English.
The collar is added last. This is ingenious, but crude. Shown here by the piece on the left, it is sewn in a straight line from the edge of the front placket, across the shoulder piece and then across the back smocking to the edge of the front placket. It means the front and the back of the smock have a split to allow your head through and the collar forms an edge on either side.
I finished the sleeves and the hem with feather stitch, turning the edges to the right side.
The result is comfortable. It won't win any fashion awards, but it is an interesting "ethnic" garment. I figure that a smocker ought to make an English smock sometime in her smocking life, if only to understand the principles of construction.
It will always look a bit 'fit-where-it-touches' because of the amount of material and the nature of the slashed neckline.
Somehow appropriate for Easter.