Most of our parcels have multiple products in them, plus gapfill. We weigh our products meticulously in Woocommerce, but when the integration pulls in orders, it does it without those weights. We weigh the finished parcels for C&D shipping weight. Then C&D uses those finished parcel weights to populate the weights for the individual products. It reuses those saved weights for suggesting finished parcel weights for future orders, and for customs weights. But it is always wrong. Sometimes it is wrong by design, overestimating shipping weight because the weight of two individually packaged products is more than when they are in the same parcel. And sometimes – usually - it is wildly wrong, due to some unknown bug that massively inflates weights. This is a waste of time when weighing and dispatching parcels because we have to delete the wrong figure each and every time. But for customs purposes, it is badly wrong. In order to dispatch the parcel we have to delete all the weights of the contents so it doesn’t flag an error. This is nuts.

Fundamentally, the weights for customs purposes in a shipment should be the actual weight of the product(s) in manufacturer’s packaging, as sold, not including the shipping packaging. It seems to me that this principle applies to all shippers, whether shipping one or many items.
So C&D urgently needs to reflect that. The best way of dealing with it is to add in some features.
1. It should be possible to turn off auto population of the weight field
2. It should be possible to import actual weights, both by file import and by API (eg. from Woocommerce). These should be the weights that are used for customs.
3. It should be possible to specify assumptions about shipping packaging. Three options: (a) based on finished weights (ie. same system as now for people who always ship one unit per parcel) (b) a fixed weight (ie. 100g per parcel), or (c) a percentage allowance (ie. 10% of the total product weights). These are added to the product weights to prepopulate/suggest a figure for shipping weight. Even though we will delete them, it is still a useful ballpark figure to alert us if say an item has been missed out.