I have seen it written, many times, that FSL should not be resized. That makes sense because one 'off placed' stitch will have a devastating result.
I have resized one or two but only a very small amount. After it was soaked, and still wet, I did try to pull it apart. If it failed, the design was not worth the thread I had used. However, if it held its own, I knew it would be just fine.
An alternate might be that you placed the design, before stitching, on a light weight fabric such as organza. If there is a problem with the design, it may hold up just fine. After stitching it out, you can carefully cut off the outside fabric, assuming that there is no problem with the outline.
Just because it is a FSL does not mean you cannot use fabric. This is why recommend a 'discovery sew' to learn what works and what does not work. If it is usable, I keep the 'discovery sew' and use them for demonstrating what I do to potential clients.
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