The author suggests 'pooling' clients as a way to curtail weasel-behavior (we only pay for injuries to the LEFT side of the body) without truly appreciating that it is just this sort of action which has lead to weasel-behavior in the first place.
Now, most insured Americans get their insurance from their employer (who transfers a portion of their wages to them tax-free in the form of healthcare services, a result of New Deal-era idiocy). Firms have no incentive to fight insurance carriers for iron-clad contracts that would make weasel-behavior impossible becuase the benefits of quality coverage do not accrue to them while the costs associated with negotiation do.
Insurers obviously prefer weasel-enabling contracts and take any opportunity to weasel because their payees (patients) are unlikely to seek other providers in the event of bad service because it would entail quitting their jobs.
Pooling insurance does nothing to improve the situation. Bueaucrats do not benefit from securing iron-clad coverage for the citizens under their charge, although they DO accrue benefits from campaign contributions by insurers. Similarly, a patient in an underserved state is unlikely to move in search of better care.
It's worth asking why weasel-behavior is less common in industries other than health-care. Why does one's bank or tailor or automechanic not engage in this behavior? Because service agreements are negotiated more carefully by those with a stake in the level of service, and because cheaters are punished by loss of business.
The only solution to dishonest behavior by insurers is individuals buying their own insurance from a wider range of independant, competing providers.