I have cut my scraps into 2" squares, 2.5" squares, 1.5" strips, 2" strips, 2.5" strips and 4, 5, 6" squares.
I was so tired of my 2.5" squares this year that I've declared war on them and want to use them up--so I'm in the process of sewing them all together---I've gotten the bag emptied the first time, so they are all at least sewed in groups of two. I'm curious how many quilts I will be able to make out of them. So far, I have enough for roughly 3-4 quilts in 9 patches made up, plus I'm making a heart quilt (out of red and blue 2.5" squares) plus, I'll have enough for I don't know how many other just squares...but I'm keeping track. When I'm finished, I'll post here.
My point it, that these were squares I was really tired of looking at, so I'm trying to use them up--then I'll start with another batch as I have another trash bag full of scraps that need to be cut down into some sort of order.
But I agree in a sense with those who don't want to do this ahead of time as this does limit you with what you can do with your scraps. As soon as you've cut that piece into squares or strips of 2.5" you can no longer make a 3 or 4" square out of it...or use it for applique, except for very small pieces.
But for me it does work to go ahead and cut them since I know I'm always making more scraps and I can just use the next group of scraps coming up for whatever that piece I needed was....