And to further blow the minds of those who's tennis and the impact on quality of life crumbles at the sight of a toe on line, I'll submit lack of single's sticks may more greatly impact court geometry than a full six inch ff. If I cared I'd do the math....
.....and the incredibly, painfully, mind numbingly obvious response to both of your preceding posts...is that both players have to play with the same height net...where as if one person is serving 6 inches inside the line, they in effect aren't.