Any catalogue is only a guide. Catalogues, especially those that are long periods between editions, are generally behind the curve, whether it's upward or downard.
Current market knowledge is extemely valuable, as is a general feel for the market. Those factors are acquired only through constant vigilance.
An opinion on how often any given note hits the market, such as the 1916 Molson $10 I purchased, will certainly influence how much anyone will pay for it, regardless of the catalogue (guide) price.
I say this with all due respect for those who set catalogue prices, based on opinions of many folks who monitor market conditions on a regular basis.
Those who buy strictly on the basis of catalogue prices will always be subject to missing notes they want, or paying too much. Those who sell notes strictly on the basis of catalogue prices risk giving them away or having them longer than they want to...