Why is the club so married to the 4-2-3-1?

Formation is a fluid thing, we rarely line up in 4-2-3-1 during games.

-In possession, one of the full backs moves up leaving us three at the back
-In defense Fred presses high and wide making us more of a 4-1-4-1
-When opening up a low block, we look like 3-1-6

With different personnel we could have other options. With Fred, McT or Sabitzer we will not have a double pivot in build up.
 
Apart from whether you’re playing with 3 CBs or 2 CFs (the latter being extremely rare, if not now extinct) I’m not convinced formation really matters that much.

What matters more is whether you’re playing deep to counter, to control possession or to press high up the pitch.
 
What matters is having players who occupy spaces (zones) at all times to maintain both a defensive or offensive structure. It doesn't have to be the same player or players. The fullbacks for example can provide the structural balance defensively.

It's mainly about having the right calibre of player within the setup, who will enhance the desired playstyle which will in-turn create a well oiled machine. So we could have a player who isn't creating loads of chances as the AM but his ability to resist and evade the press could well result in opening space for others to thrive and hence could enhance the quality of the team as a collective.
 
Arsenal who are top of the league play 4231 on paper. But formations are a bit of a myth nowadays. It’s all about positional play.

Just look at Zinchenko who plays in midfield with posession and at left back when out of posession. Same with xhaka and Odegaard who have very different positions in and out of posession.

The more important part is being in the right positions at the right time.
 
Formations are fluid.

Most of the time, the shape differs drastically when in possession, when out of possession, etc.

We should adopt a 3 man midfield though with 2 number 8s ahead of a 6 instead of shoe-horning a #10 in there. I'd be tempted to cash in on Bruno.

Hit the nail on the head, even though I would argue the current meta is evolving to actually have 4 in midfield, a 6 and 8 behind two 10s basically. On paper they often come in different shapes but I guess the formation Tuchel played is probably the closest to how the top teams shape up in an attempt to gain back midfield dominance against 3 man midfields.

Tuchel pretty much lined up with that box in midfield while other managers like Guardiola and Arteta pull one FB centrally to form the double pivot behind the two 10s.
 
I think we'll eventually transition to a 4-3-3 but it's difficult to do so with the profile of this squad. Whenever Bruno Fernandes plays we're likely to be lumbered with the 4-2-3-1 because he can't really play anywhere else. If he hadn't been given that contract which doubled his money, we might've been able to move away from it sooner.
How do you defend when the opposition has the ball? That's your formation. Most teams are 4-5-1, 4-4-2, or 5-4-1.
 
4-4-(fckin)-2 with Benson and Hedges up top, everyone knows that is the way to play football, England 1966 proved that!
 
I don't think formation matters as much as the players you put in the roles and what their game is like.

For example, if we played 4-2-3-1 with Eriken or Sabitzer in the "number 10" role, they're both outright CM's and play as such, so that is essentially no different to a 4-3-3 on paper, whereas if you play Bruno there, or Wout as we have been doing, they play as essentially forwards rather than midfielders, so that's more like playing with just two CM's.
 
This notion that we play a specific formation....

We are about as fluid as I have seen us. The only time I see us in a 4231 is on the TV graphic line ups.

Formation is a fluid thing, we rarely line up in 4-2-3-1 during games.

-In possession, one of the full backs moves up leaving us three at the back
-In defense Fred presses high and wide making us more of a 4-1-4-1
-When opening up a low block, we look like 3-1-6

With different personnel we could have other options. With Fred, McT or Sabitzer we will not have a double pivot in build up.

There was also one game recently (can't remember which one), where for a period Shaw was coming in and sitting central creating a somewhat 325. Our full back movement is quiet interesting to watch.
 
It's been said a lot, that there even barely are "formations" such as rigid as they used to be.

 
It's been said a lot, that there even barely are "formations" such as rigid as they used to be.


I said that pages back and I’ve said it on multiple occasions in other threads. Majority of football fans don’t and will not ever understand this because they never even go to games to see it with their own eyes. The TV says 4-2-3-1 so that’s what it is.. heck even the BBC website routinely has starting positions and formations wrong..

With people so stuck in the past I’m surprised no one has suggested using the WM formation. With a bit of Hoofball it might be viable again.