In the situation presented, does the visible sign warn you of two dangerous bends, the first of which is to the direction indicated on the sign, and the second of which may be to the left or to the right?

No. The visible warning sign A-1 'dangerous bend to the right' indicates an approach to one dangerous bend. A sign warning of two dangerous bends (e.g., A-3) has a different symbol, depicting two successive curves in the road.