I don't cut my scraps. I sort them by size to be cut later for whatever project I'm working on. If I need 2 1/2" then I look in the 2 1/2" box and the 5" box.
What if you find a pattern that uses 3 1/2"? Also if you cut things down to 2 1/2", then you will get an awful lot of waste on some pieces.
Having said all that, everyone has a system that works for them and makes them feel more organized, so it's just a humble opinion
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