A great video from Adorama abeit some plugs but awesome nonetheless. Thank you for sharing.
The writer appears to be approaching from an accounting standpoint of pricing via measuring cost which is logical and sound. If more photogs both pro's and amateurs can do this the industry will be a better place for all.
Just to add; an observation of mine is that most people try to price their rates based on what they think they would pay if they are the client. Then their own cheapness creeps in, "oh that sounds expensive, nobody's gonna book me at that rates, I wouldnt myself" No, no! NO! Remember, creative work is not a commodity, it's not like buying a drink or plate of rice.
Your price should always be something that you could not afford if it is yourself. Then you will make progress. You should be marketing to clients that have more spending power than you and thus should not allow your own emotions limit your price. I guess a large part of the reason behind is that many amateurs and part timers are salaried employees and do not have the mindset of a full time self employed career photographer.