"Jack W" Windswept@Home wrote in message
...
Included were three pieces of plywood sheathing to possibly replace
three "soft" spots of the existing sheathing.

Two of the pieces are nice and flat but one is curved along the length
like a parenthesis.

Is this piece useless for roof sheathing, or will they drive nails
lengthwise down the center to flatten the board to the rafters??

Forgive my ignorance in this regard and thanks.

Not a problem. Once nailed in place it will be just fine and plenty sturdy.
It is getting harder and harder to find quality wood and sheathing grade is
one of the lower types.