I don't think of you as a poster child. If anything, more as an example that can help others (and each other) better understand all the dynamics at play. It's still hard to pin down precisely, since I'm not sure the exact time you executed the trade, especially since there was already quite a bit of volatility around that time as we discussed. I'm also getting the feeling SBD may have already been trading back near $1 USD on the internal market around that time as well.
Something else I noticed here on steemwhales: https://steemwhales.com/valued-customer
Date Steem Steem Power Steem Dollars Estimated Value
2017-07-08 68.577 (0.01%) 9.870 (0.00%) $211 (-17.25%)
2017-07-07 60.001 (27.15%) 68.573 (8.89%) 9.870 (1,065.29%) $255 (28.14%)
2017-07-06 47.189 62.976 (0.01%) 0.847 (-99.23%) $199 (-25.75%)
2017-07-05 0.000 62.972 (0.00%) 110.045 (0.00%) $268 (10.29%)
Notice how your balance fluctuated from $268 to $199 to $255 to $211 in over those 4 days. Also notice how 13 STEEM seemed to be missing from the $199 day (total 47.189 STEEM), only to reappear the next day (60.001 STEEM). What I think happened here is that the two last transfers didn't register until the next day, and may not have been included because they were still on the order book from the previous day:
8 days ago Paid 0.126 SBD for 0.069 STEEM <-- did not register until 2017-07-07
8 days ago Paid 23.191 SBD for 12.743 STEEM <-- did not register until 2017-07-07
8 days ago Paid 0.653 SBD for 0.359 STEEM <-- registered 2017-07-06
8 days ago Paid 61.878 SBD for 34.000 STEEM <-- registered 2017-07-06
8 days ago Paid 23.350 SBD for 12.830 STEEM <-- registered 2017-07-06
So the good news, at least, is I believe that accounts for the additional discrepancy you were seeing, and you really didn't "lose" nearly as much value as you thought! :)
Thanks again for providing a new source of good information that can help me to understand this issue. Steemwhales was not familiar to me.
The fluctuation in the reported value of my account reflects accurately my confusion over exactly how badly that trade failed, and why I had to estimate a very wide range of potential loss.
Ultimately, what I learned from this experience is that I shouldn't expect to profit from trading activity without good understanding of the underlying mechanisms, and good data, both of which you have raised.
Thanks!