Sean:  I have been looking at the -$141K P&L hit in "Other Changes" on 8/13/01 you were inquiring about.
The biggest "contributor" of this hit is the restructured Modesto deal # 520328.3, which alone caused -$130K in Other Changes (a.k.a.
2nd Order in financial terms).
I believe what happened is that Matt re-marked the daily volatility curves down by a significant magnitude on 8/13/01 (* please see curve managers for the change).
Usually when volatilities changed drastically they would disrupt financial evaluation models and more likely to cause a change in deal value by factors which cannot be explained (i.e.
Second Order).
This doesn't necessarily mean that the evaluation is incorrect but just that there will be some value change for which the models cannot pinpoint the reasons.
Anyway, for this basis option deal you lost $94K on 8/13, and this -$94K can be broken down into Curve Shift (-$19K), Gamma ($1.5K), Vega (70K), Theta (-16K), and Second Order/Other Changes (-$130K).
I looked at the curve change and interest rate change between 8/10 and 8/13 and they are relatively insignificant, but the drastic volatility mark down makes me feel that your losing money in this deal is somewhat consistent w/ what we should expect.
I am still working with IT to see if we can nail this down to give you a more specific explanation.
In the mean time, if you have any thoughts or concerns, please feel free to let me know.
Thanks,

-$141,000 P&L hit on 8/13/01