@roger,
Be careful of studying it too hard. Your head will spin and you could fall down and hurt yourself, Roger.
By the way, I was sitting around with some friends, drinking...I mean THINKING, about how to explain what a "derivative" is. A lady at the table came up with a variation of this as a start.
"Roger and me" assemble a baseball team of professional players (= loans). We sell shares in the team (= a bunch of loans) to investors, telling them that it could be a great investment. There is a lot of small print about Ican being out in left field while Cyclo is in right. All that is disclosed and it is up to the potential investor to note that.
Meanwhile, "Roger and me" are giving other folks the opportunity to bet on how the team will do . That bet is the "derivative."
Roger may or may not warn bettors that some of the players (loans) don't look too good.
In the Goldman case, they are accused of putting together the loans and then advising clients to bet against them.
The case against Goldman is strong, popularly. But it was up to investors to read the fine print. I would have put H2O man in left field.
I am not sure this post adds anything but I started composing it while I was at the dentist today.