Whilst the weight will probably  not assist in winning the claim directly,  it will definately assist in any police investigation on the matter. If you have that then you can scare the wits out of the buyer with it which of course may assist with winning the claim!

This is where my use of e-parcel is fantastic as I have the weight to the gram on every big order and its shut down a few arguments. I dont think you get exact weight on click and send? could be wrong of course