Why Tottenham keep on improving and Man City are struggling - Jermaine Jenas I am not surprised that Tottenham are doing so much better than they were at this stage last season, because I always thought what happened to their players when Leicester went on to win the league would help them go on to the next level this year.
Spurs face another big test at Manchester City on Saturday but they will be full of confidence after putting in one of their best performances of this campaign when City came to White Hart Lane at the start of October.
Back then, City had a 100% record in the league under Pep Guardiola but I still thought Spurs would beat them, and make a statement of intent.
They did. I also said then that
I thought Mauricio Pochettino's side would go the distance in the title race this time, and part of the reason I felt that was because the experience of being in one, and losing it, builds strength of character.
Their younger players like Dele Alli and Harry Kane have developed in other ways too. They have both taken a step up, in fact the whole team has.
'The most powerful central midfield in the PL' Spurs have had some criticism over some of their summer signings, but you do not need to go and buy lots of players when the ones you have already got are dramatically improving year on year.
I still think their squad is stronger now, though, especially in the central midfield which is key.
Last season, when Eric Dier and Mousa Dembele played together there, Spurs looked solid - they only lost one out of 26 league games with them both in the team.
In the games I saw, it was not the same whenever Pochettino switched things round in that department. The tempo dropped and it seemed some of the team's belief disappeared too. They lost five of the 12 league games they played without at least one of them.
So the addition of Victor Wanyama,
who joined from Southampton for £11m in the summer, was massive.
Having Wanyama there means Pochettino can play Dier at centre-half without losing anything in the middle of the park.
Far from it, in fact, because Wanyama and Dembele have formed the most powerful central midfield partnership in the Premier League.
The other reason I think Spurs have progressed is their manager. Pochettino has gone up a level too.
Antonio Conte has rightly been given a lot of praise for his results in his first season at Chelsea after switching formation in September to play with three at the back.
But he has used that system throughout the majority of his coaching career, and he knows how it works.
It would have been more of a surprise if Conte had come to England and played with a 4-4-2 or 4-2-3-1 and cracked the Premier League that way.
Nobody expected Pochettino to play with three centre-halves - before the start of this season he had only done it on one occasion since he arrived in English football with Southampton in January 2013.
But he has now used it five times since the start of November, starting
with the derby against Arsenal at Emirates Stadium, when Spurs were struggling in the Champions League and missing several key players.
Everyone said it was a good time to play them, but Pochettino switched things round, got an unbelievable point and almost won the game right at the end.
Since then, Pochettino seems to be able to switch between a four and a three whenever he likes and be as successful. That has allowed him to adapt his side as the season goes along, reacting to where they were struggling.
The loss of Jan Vertonghen for a few weeks with an ankle injury is big because of the stability he brings to the team, but I am sure Kevin Wimmer will slot in pretty smoothly if they continue with a three.
Pochettino's sides are always solid at the back but a few weeks ago he felt as if he wasn't getting as much out of his attacking players as he could, and that is not the case now with that formation.
No weak links in Tottenham's strongest XI While Tottenham don't have the strongest squad in the Premier League, I can understand why some people think they have got the best team.
When everyone is fit, they do not have a weak link in their strongest XI - everyone fits perfectly together into their style of play.
Spurs clearly have some outstanding individuals too of course. Hugo Lloris is arguably the best goalkeeper in the top flight - I don't think you can split him, Thibaut Courtois or David de Gea.
For me, Danny Rose and Kyle Walker are by far the best full-backs in the league and I said last season that I saw Vertonghen and Toby Alderweireld as the two best centre-halves.
They are definitely the best defensive pairing in the Premier League anyway, but I am still confident Spurs will be able to cope while Vertonghen is injured.
As I have already said the midfield unit is extremely strong, and you could make a great case for Harry Kane being the best striker too.
Kane won the golden boot last season and is on fire at the moment too, but if I were to dissect every single position then there would be players from other clubs that, on paper, are better than what Spurs have got.
Having them instead might weaken Tottenham as a team, though. For example I would have Eden Hazard ahead of Christian Eriksen but without Eriksen you might lose some of the things that make the whole team tick.
Eriksen does not give you everything that Hazard would but he and Dele Alli have just started to get their almost telepathic understanding with Harry Kane going again.
The way those three link up is a good example of why Spurs are doing so well, and all over the pitch they have units or partnerships that have the same sort of understanding.
Why City are struggling in defence and attack The biggest contrast between City and Tottenham at the moment is at the back. I think that is because unlike Pochettino, City boss Pep Guardiola does not have the players to play the way he wants to.
Guardiola has also tried playing with three centre-halves but it did not work because he used Raheem Sterling and Leroy Sane as his wing-backs when they do not suit that role.
In the centre of defence, City have not found a partnership that is anything like the one Vertonghen and Alderweireld have either, and it does not help that they constantly chop and change their backline.
Guardiola has been tweaking things in attack too and, again, I am not sure it has helped some of their players.
Kevin de Bruyne was playing brilliantly at the start of the season, creating chances, scoring lots of goals and also winning the ball, but that was when he was playing centrally and he did not have the same impact when he was pushed wide.
I don't get why Guardiola did that. In September he was talking about
De Bruyne being second only to Messi in terms of players he has coached. Well, you don't move Messi, do you?
Sergio Aguero has not been his usual deadly self in front of goal recently either, and I think he has been up and down all season.
Aguero has been sent off twice, including the retrospective red card he got against West Ham, and both incidents came through frustration.
You would not want to take that will to win out of his game because it is part of what makes him so brilliant but he does not look like a happy player at the moment.
That might be down to the system, but he is so good that at some point he will find form again and really take it out on the opposition - I just hope it is not Tottenham who take the hit.
Tottenham are flying at the moment - on a six-game winning run in the league, scoring goals for fun and probably playing better than ever under Pochettino.
They will have seen the way Manchester City have been defending recently and it will fill them with confidence ahead of their trip to Etihad Stadium on Saturday, as will the results of their recent meetings - Spurs have won the last three.
When they met at White Hart Lane in September, I knew Pochettino would look to press high up the pitch, and I looked at the way City were playing and thought it would play into Tottenham's hands. It did.
On form alone, I should probably be even more certain of a Spurs win this time, but the thing that keeps sticking in my mind is Guardiola's pride.
It has taken a massive hit in the last few weeks, especially in
last week's 4-0 thumping at Everton which was his heaviest domestic defeat in more than nine years as a manager.
People like Pep are seriously dangerous when that happens, because they are born winners.
Just when you think things are going to get really hard for them, they dig deeper and find something within themselves to make their situation drastically different.
City have got lots of world-class players who can win games on their own. They are not playing particularly well at the moment, but it only takes one of them to perform on Saturday, and Spurs could be in trouble.
Jermaine Jenas was speaking to BBC Sport's Chris Bevan. 
