RSA Golf-rules allow 3 options the player can choose from after having declared a ball unplayable:
by adding 1 stroke penalty, he can:
- replay the ball from where he was before
- drop a ball on the line pin -> ball further away as far as he wants.
- drop a ball within 2 clublength from the ball not nearer to the pin.
The improved drop options allow only option 1 and 2, but no drop within 2 clublengths. (This will be needed for the lateral water-hazards as well, once these are defined!)