The statement before yours is a correct understanding of what a CDS does.
No, it's not actually. CDS was written on particular bonds. Not counting marked-to-market collateral arrangements, no money is due from the seller of the CDS until the bond takes either principal loss or an interest shortfall. Depending upon where the bond resides in the capital structure, this could be years after the deal turns to crap and the bond drops precipitously in value.
You are aware that Lehman failed due to its risk exposure to mortgages including CDOs, right?
Lehman failed because it couldn't roll over its repurchase agreements, i.e. financing arrangements. It was akin to a run on a bank. CDOs are securitization trusts where the components are actual bonds, rather than individual loans as in a plain vanilla securitization. They did not generally involve CDS. There were things called synthetic CDS which were CDOs composed of nothing but CDS on bonds. These were created mainly so hedge funds could construct short positions on the housing market. As far as I remember or understood at the time, CDS was not Lehman's problem. It was its inability to finance. I suppose to the extent that their cash portfolio was hedged with CDS, that would have created a cash flow problem because the CDS did not go down as much as the cash bonds and wouldn't have provided a sufficient marked-to-market collateral flow to match what was needed to meet margin calls on their repos.
You are aware that investors bought gob loads of CDS protection specifically written on the default of mortgages including CDOs, right?
It paled in comparison to the size of the mortgage bond market, and, in general, the investment banks Bear, Lehman, Merrill, Morgan Stanley, and Goldman, were long CDS, not short CDS. That is, the CDS was helping to stanch their losses.
And you are aware that AIG failed (was bailed out) two days after Lehman brothers went bust, right?
Well, AIG failed because Lehman failed. Once Lehman failed, the market went into free fall, and all of AIG's CDS got marked against them enormously, which exceeded their cash on hand. It was unnecessary to bail out AIG, by the way. It was done at the behest of European banks and Goldman Sachs who stood to lose tens of billions if AIG couldn't meet their collateral calls.
Regardless, the point is that CDS was rather late to the game in helping facilitate the housing bubble. The main driver was the securitization machinery which helped create $3T of so-called AAA spread product, which didn't deserve to be rated AAA.
And you agree that:
So I dunno why you're trying to disconnect parts that you don't want to "blame".
Because I feel most people don't understand CDS (I suspect you don't for example) and malign it unfairly. I was there at the start of the CDS market in the late 1990s (it started with Emerging Market debt trading), and it is a very useful tool. Interestingly, when Lehman failed there was a lot of worry that the CDS market on Lehman would break down because there was an enormous "float" of CDS written on Lehman. In the event (and I fully expected this at the time), the market cleared beautifully. Participants in the market had for the most part kept their net positions manageable.
CDS is not a fundamental risk in finance. Leverage is a fundamental risk. CDS can be used to create implicit leverage, but they are still less risky than an equivalent amount of explicit leverage using financing. Your lenders can always pull your financing (as they did with Lehman) and force you to sell at an inopportune time. They can't do that with CDS.