I looked around for the article, but couldn't find one except for the May article on Mike who previously guaranteed to sell your house. He, like most Realtors, offers to terminate your listing agreement early, if you're dissatisfied. I don't know of any Realtor who won't terminate a listing for a dissatisfied client. But he thinks that's special treatment worthy of advertising. We consider that the normal course of business - treating customer right.
Please be aware that it is prohibited for a Realtor to put a sign on a property for which no written contract to sell the property exists. Yes, a contract must be written. This is a consumer protection provided by state law. The offering for sale without a written contract could lead to things like people just putting For Sale signs on anybody's property and "Selling" it without permission. Imagine the fraud that could happen otherwise.
Please remember that termination of the agreement does not relieve the principal from paying a commission. So, if a buyer shows up and the seller terminates the listing, seller is still obligated to pay the commission.