I agree that appraisals will justify a property using solds, but the problem with that mentality is that in the end, value is established by the seller and the buyer coming to an agreement (tempered by the appraisal in the case that there is an appraisal... i s'pose), not between the buyer, seller, and a bunch of other sellers.
That said, if you are pricing your property to sell, figure out what other active properties are on the market, and price just under the lowest priced property that is similar to yours (try to take subjective factors(E.g. View, location, design, etc.) into account as well as objective ones.) If you price based only on sold listings, then you aren't putting yourself in a competitive position, unless you initially price based on solds/pendings/appraisal/objective factors, and then adjust based on the competition in the market.
If we look at it in another context, how do car manufacturers price cars? Certainly not on what the last 10 similar cars sold for. They price them based on what similar cars are selling for on the market. Gold works the same way, as do Tshirts. Why would the housing market be different?
As far as appraisals go, can't you challenge them? If you can justify your price based on objective/subjective factors in a CMA, who says you couldn't challenge the lower appraisal with your CMA?
I'm sort of just rambling here, but I feel that this guy actually has a good point, that most people don't acknowledge.