[Yoda]

I questioned why Homer never discussed wrist positions at the top (cupped, flat, arched etc.).

The ideal Wrist Positions at the Top are depicted in Photos 5-C-1 and 5-C-2.

The Horizontal Wrist Conditions -- Flat Left and Bent Right -- are established at Impact Fix and are present from Start Up to the end of the Follow-Through (Both Arms Straight Position). These alignments are integral to the Flying Wedges Assembly (6-B-3-0-1).

At the Top in Full Strokes, both Wrists are also Turned On Plane (Rotational Motion), and the Left Wrist is Cocked (Perpendicular Motion). The Right Wrist remains Level throughout the Stroke.