Dear Eelco,
If you copy a Sales Order from an existing Sales Order the pricing changes which were done in the original Sales Order (e.g. the discount which was passed on from the Sales Quote) are taken over in the new Sales Order.
Also any changes which were done in the meantime in the product or account master data will not be considered as Changed Master Data is Not Taken Over Dynamically in existing Sales Documents and new Documents which created as a Follow-up.
Since the approval process for Sales Orders does not take Discount into consideration (like it is for Sales Quotes) the Sales Order will not be sent for approval. In regards to the pricing the you could update the pricing in the new created Sales Order.
You can update the pricing by clicking on the Update Pricing button in the Total Pricing section.
If you select the option Completely all manual changes will be discarded and it triggers a complete new pricing on the basis of valid pricing master data and cost valuation relevant for this particular document.
All manual price component adaptations are discarded.
If the you want an approval for Sales Orders which checks for discount you need to change their Sales Order approval process condition accordingly.
regards
Arya