Collectors, in all fields, tend to fix a limit in their mind of what they will pay vs catalog value.
eg some will never pay more than 60%
some will pay 100% if it is the last they need for a set.. etc etc etc

Providing a guide is consistent in the way its values were derived, it has other important uses:

- Reference listing of chips known
- In the case of TCR, unique numbering system
- Fair system of 'values' enabling comparison between one chip and another. If one chip is $50 and another is $200 then you got your info that the $200 one is much scarcer and arguably worth 4 times as much. The fact that some might argue, for example, that catalog prices look like they are 20% above the norm is irrelevant. Figure those two chips in your mind are $40 and $160. One is still 4 times the other
- Emphasis on making sure prices are adjusted fairly for 'finds' and quoted reasonably for new discoveries based on quantities known, and not guesses of what might exist.

Anyone who buys a catalog merely to work out how much their collection is worth is in the wrong game IMO

Jay and I are editing TCR at present. Jay has extensive data on pricing from the past 6 or 7 years. That data is being heavily used in determining prices for TCR11. I am having little input into the pricing. As a dealer/seller, I have been using Jay's data for my own pricing for years anyway.