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Darthknight used the memo of the Binance account of blocktrades. Which makes him at least very related to blocktrades.
So if you use the method described above (picture), you would still use your OWN Binance memo, and not the Binance memo of Blocktrades (the exchange I mentioned). Doesnt make sense darthknight uses the memo of blocktrades if he is not the owner of that Binance account.
Darthknight is not BUYING, he is SELLING. Otherwise it would have been a transfer from block to Darth, not the other way around.
If I would sent 100 steem to blocktrades, I would use MY OWN Binance memo to get it in MY wallet.

Darthknight used the memo of the Binance account of blocktrades.

What makes the memo "the memo of the Binance account of blocktrades"?

If I would sent 100 steem to blocktrades, I would use MY OWN Binance memo to get it in MY wallet.

No, this is not the scenario I am describing. If Darthknight was BUYING STEEM with another token such as ETH or BTH, and having their STEEM sent to the Binance exchange, then the purchased STEEM would be going out of the Blocktrades account into Binance.

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