You need to be very careful when doing this. It is too easy to lose points if you have to take off more than a little sliver of fabric.
Another example of why this is not a good idea:
9 Patch block
If you want it to come out at 9" finished, and you cut the squares larger than 3 1/2" the center block will always be larger than the outer blocks. There is no way to cut them all larger and have the cemter block be the correct size.
This will be the same issue with any multi piece block.
You can make a 1/2 sq triangle slightly larger and then trim, but as to other blocks, I would be very careful and think about it first :D:D:D