Chelsea are on the right track, but to say that they are improving is not right. the result against Tottenham Hotspurs can be deceiving for their players, it could be a good boost for their mental, but also could trigger complacency in the squad. I think poch knows that they than that to win their next games which are getting harder and harder because other teams pay attention towards Chelsea's progression.
Game against Mancity is the biggest test for Poch and Chelsea as a team to know if have they found their character as a team or just still raw. I think the result will show how far they have become.
I agree with you the result against Tottenham may be much of a deception than doing them good because considering the circumstances around they game, they wouldn't have won if all those didn't happen, and so they shouldn't expect same to happen with them playing other teams.
Manchester city is really going to be a really tough test for them because Manchester city is in their perfect form and can at this point play against any team as proven in the UCL and premier league aswell, but Chelsea don't seem to be in such form that is well enough to challenge Manchester city, after Manchester city, they will be facing Newcastle so it's going to be more like a series of drill, let's see how well they can survive this.