I think you are being very generous to call his comment "obvious humor". A number of the people in that comment stream missed the humor, and pyon gave no indication (such as a tone indicator) that it was humor.
Operations can incur some kind of "debt" which a more expensive operation occurring later has to pay for. Or they can be regarded as enjoying something "prepaid" by an earlier expensive operation until the credit runs out and another prepayment has to be made. Possibly, either view can be used to arrive at the same result.
The level of contention on the part of Pyon is disconnected from the level of detail given to "amortized" in the article and based on the false premise that the word "average" implies some kind of order that is contrary to "amortized". (Expert, my foot).
It is factually correct that a an amortized performance is an average, but readers should be aware that it's a special kind of average (not every average is "amortized") and that it is a warning label: an algorithm with performance quoted as amortized possibly exhibits a big latency spike that occurs infrequently.