Item specific shipping - a way to bin smaller and higher cost items using weigh bins

Was struggling to find a way to create shipping bins that met the criteria below for my online store.  It combines the flat fee + additional item discount and allows for binning smaller and larger items and their cost.   You basically assign weights independant of actual weight to make it work with some caveats.  Thought I would share to hopefully make someone else's life easier since Squarespace is not prioritizing advancements in shipping options like Shipping Profiles in Etsy.  The attached spreadsheet shows the bin settings.

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