Whether or not you agree with Yip, he is correct from an economics standpoint.
All supply/demand curves are usually smooth.
If you raise the ticket price from from 99 to 109, you will lose some passengers - that is simple fact.
The question is HOW MANY you will lose. Half a percent? Three percent?
The supply/demand curve can predict that outcome somewhat.
But that is not the whole story - since more revenue is made on the passengers that remain, total profit may increase. Or remain the same. OR decrease.
Every link in the supply/demand chain of air travel must participate in the supply/demand pricing.
There is no way to permanently insulate pilots from the variances in pricing. Right now, the US is entering a period of wage deflation. Since all pilot/company bargaining is accomplished by human beings, the pricing of the labor of those people WILL be subject to those economic laws.
You may as well get mad at the weather.