ssorrow

This is probably a dumb question but can you use a 1/2" seam allowance on some of the blocks in a quilt and 1/4" on the rest of the quilt without messing everything up? I have never made a quilt and I'm trying to follow a pattern.

I'm using 5" charm squares for most of the quilt but the pattern also requires that some of the 5" charm squares be subcut into four 2" squares. These subcut pieces are then sewn together into a 9 patch that is supposed to come out the same size as the 5" charm square. I used a Sizzix die to subcut the squares but realized the die if for 2 1/2" "unfinished" squares -- not 2". Instead of having to cut all of these little squares down into 2", I wondered if I could just use a 1/2" seam allowance on these blocks. Hope I have made sense in what I'm saying.