BGC
There are two versions:
The override version will override the original Lucky Man Folded Shirts. The original swatches will still be there, and my swatches will be added to the same catalogue item. (I prefer this because if you have Laundry Day, my shirts will sometimes show up when Sims put away laundry!)
The standalone version is just my swatches, as a separate catalogue item.
You can have both in your game at the same time (no conflicts), but there's no reason to do so.
I just wanted some extra swatches to make these shirts more useful as decor/clutter. They always end up sitting on my Sims' dressers! The plaids and patterns came from the mothz pattern pack.