A big potential problem is share distribution and its effect on the claim pool. Since ownership of shares in the DAC insurance policy is anonymous, how can I as a consumer trust that my risk exposure won't fluctuate wildly if someone who holds a significant portion of shares has a large but valid claim.
For example, say the claim pool is around 5% of total, on average. I buy shares expecting ~20x their BitUSD value in return if I need to make a claim. Then someone holding 20% of the total shares makes a valid claim which is then added to the claim pool. That 5% jumps to 25% and now if I need to file a claim then the maximum I can expect is ~4x the BitUSD value of the shares.
Insurance is all about mitigating risk and traditionally when you buy a policy you know what your premium is as well as the maximum claim amount so you can quantify your risk exposure for the asset that's insured. With this Insurance DAC, while your premium is fixed, the maximum payout has the potential to fluctuate wildly which is counter intuitive to the entire purpose of buying insurance in the first place.