What does Cash's list of the thirteen reasons for beveling the edges of the coffin tell the reader about him?

Through Cash's
description of making his mother's coffin, the reader can tell that he is very meticulous and
also has a difficult time dealing with her death. Instead of engaging directly with his
emotions, Cash prefers to detail the reasons that he produced the coffin the way he
did:

I made it on the bevel.

1. There
is more surface for the nails to grip.

2. There is twice the gripping-surface
to each seam.

3. The water will have to seep into it on a slant. Water moves
easiest up and down or straight across.

4. In a house people are upright two
thirds of the time. So the seams and joints are made up-and-down. Because the stress is
up-and-down.

5. In a bed where people lie down all the time, the
joints...