The evidence suggests that those blemishes have been eradicated. Including the climax of last season, a ninth consecutive top-flight win equals a club record dating back to 1912. Even a statistic like this, on the back of three penetrating performances, will not make City's manager, Manuel Pellegrini, giddy.
You get the impression that if the Chilean won 38 successive matches he would engage with interviewers with the kind of straight bat an Ashes cricketer would envy.
"What is most important is the next game," said Pellegrini, sounding rather like a curmudgeon telling a room of over-excitable youngsters to turn the sound down.
You can admire the professionalism, but he must be dancing inside given the flavour of this comfortable two-goal victory thanks to Aleksandar Kolarov and Samir Nasri.
Trips to Goodison Park are among the most accurate measures of title credentials. This is a venue where mental agility is assessed as much as skill. City have never lacked the latter in the Abu Dhabi era, but it was their temperament that was suspect when they failed to defend their crown last season.
The criticism under Pellegrini is he has built a team who play only when the mood grabs them. If they are in this frame of mind for the next eight months, no amount of panic buying by rivals between now and September 1 will stop them.
You would need a lengthy forensic examination to find a weakness in this City team over the past 270 minutes. Even the problem of Yaya Toure's propensity to have a breather mid-game has been resolved, with Fernandinho now looking like a midfielder who ought to have cost £29 million.
Eliaquim Mangala and Vincent Kompany were as much a foundation of this victory as the razzle-dazzle of the attackers.
Everton were reduced to sporadic attacks, Romelu Lukaku's free-kick that clipped the crossbar at halftime the only genuine scare.
When the goal arrived on the hour, there was a certain inevitability that Raheem Sterling was involved, teeing up Kolarov to beat Tim Howard at the near post.
Everton boss Roberto Martinez correctly identified the opening goal as the moment the balance of power irreversibly shifted in City's direction.
"The first goal seemed too important today," Martinez said. "We knew we were playing against a quality team and the first goal affected us too much. It is a real bad moment, we were really sloppy on the ball, give them a counterattack and the ball ends up in the net. We weren't clinical enough."
Nasri's clever chip over Tim Howard a minute from the end secured the points and City left Merseyside looking even more formidable than they did on arrival.
City's performance will serve only to affirm to Jose Mourinho at Chelsea and Arsenal's Arsene Wenger how much more needs to be done if they're to keep up with the leaders.
The race is long, but City might already be planning the bus parade by the time the others match this form.
Manchester City 2
Everton 0
