One way to implement a token-based discount is that whoever owns/holds a token gets the discount. Another way (that I had in mind) requires you to transfer it back to the store. In this case it is lot more convenient to transfer both BTC and Counterparty token in the same transaction.
You're right, although not requiring the asset be sent back to the issuer would seem to be a weaker option. Asssuming ownership of the discount token is checked based on the identical address sending BTC (and the store doesn't implement any limits on validity period of the discount coupons), the owner of that address could keep replaying the discount or proxy offering the discount service to others without the token (sort of like cardsharing in the sattelite world ), right? there would seemingly be less incentive for many people to own the discount token themselves . Agreed that it is more convenient to send both in the same tx.
You could have a scenario where you're dealing with store value coupons rather than simply discounts. Either they permit you to buy a specific product/service at the store or they permit a certain dollar spending credit at the store/service, in that way you may never require btc at checkout time.
Does anyone have the time or skills required to follow all the burnt BTC at the 1CounterpartyXXXXXXXXXXXXXXXUWLpVr address back through the history of the blockchain to see when they were mined?
It would be nice to visualize the timespan over which the POW period of Counterparty occurred. Afterall, you can't have Proof of Burn without Proof of Work (in this case).
You mean the time the transactions in the counterparty burn were 'mined;, or the original mining of the coins that were sent to counterparty?
if the former, it was simply defined in the protocol and you can see from any block explorer- first XCP was possible to be mined from block 278310, although the first earned in mainnet was in block 278319 (
http://btc.blockr.io/tx/info/685623401c3f5e9d2eaaf0657a50454e56a270ee7630d409e98d3bc257560098), last XCP was possible to burn at block 283810, and people were burning right until the end (indeed after the end too)
if you would like to trace the origin of the coins sent to take part in the PoB you can use a method like one described in the paper below
http://143.225.81.37/www.mobilab.unina.it/tesi/Giuseppe_Galano_A_Visual_Interactive_Realtime_EXplorer_for_Bitcoin.pdf