It could easily, as City manager Pep Guardiola noted, have ended with seven or eight goals for the home side who even without the injured Leroy Sane and Gabriel Jesus were close to unstoppable.
"At times tonight I wanted to give my players a cuddle because I felt sorry for them," West Brom manager Alan Pardew told reporters.
Having watched his side struggle, like so many others this season, to cope with City's swift breaks and precision passing, Pardew had no doubt who was the central figure behind the torment his side suffered.
"De Bruyne is the key to it, because his passing and offensive play from deep is of such high quality, you don't quite know what to do with him," he said.
The Belgian's ability to find a player on the move with a perfectly-placed and weighted pass carved open West Brom's defence for the 19th-minute opener.
De Bruyne found Fernandinho, who had burst into the inside left channel and slid the ball past keeper Ben Foster.
Foster could have been, on another night, the hero for West Brom, and he produced four fine first-half saves to keep out powerful strikes from De Bruyne whose ability to find the target from distance is equal to his speed on the counter and accuracy with the ball at his feet.
When De Bruyne did beat Foster he was foiled by the top of the crossbar but the Belgian got his reward after the break.
Bursting forward from inside his own half, De Bruyne kept his feet despite a lunging attempt to bring him down from James McClean and played a neat exchange of passes with Raheem Sterling before sweeping the ball home.
Sterling was the provider again for the third, slipping the ball through to Argentine Sergio Aguero who lifted his finish over the advancing Foster in the 89th minute.
"It was a nice performance, top performance, we deserved to win. Three more points," Guardiola said.
"All season Kevin de Bruyne has played an outstanding level. If one of the best players run and fight like Kevin does the rest follow him."
(Reporting by Simon Evans; Editing by Toby Davis and Ed Osmond)
