Grass That Cuts Itself

I have just thought of a great idea for the Bio-Engineering companies. Create a grass that cuts itself.
Imagine creating a grass that has quite sharp edges: if you have whistled through a grass to make a sound - you will know that grass has very much an edge.
As it grows, it sways in the wind. When it does so it creates a sithing action, if the engineers could genetically modify the core of the grass to help it twist and bend as the wind blows. When it does so, any other grass blades around it get cut. This brings in competition between blades of grass in the same clump.
If a blade of grass grows taller, it immediately gets chopped by lower grass blades as it is so tall it can no longer sway down to cut the lower grasses. A computer model to simulate this ability would be interesting: similar to Life.
So eventually with the help of GMO we can have swathes of grassland cutting itself and sheep and cows can take a rest and just hoover the grass up in stead of ripping it.
It might be a bit tricky if you wanted to play football as you would end up with a load of paper cuts!
But at picnics, you would never be lost for a knife!