Saints ST holder here, do not usually comment on other fans forums but I was browsing prior to our game at the weekend and found this thread and thought I would share what I know, heard, read, etc.
What happened in the summer was a shock to us all and to be honest most of us were bricking it and felt sick, confused, angry etc. The board however did tell us (whilst the press was doom mongering and some others were stirring it) that we should wait until the close of the transfer window before judging them and the board were pretty consistent with their message in fairness to them, always stating that we would get a good manager as a replacement and they would reinvest the money, but they needed time to get things in place and our patience. They were right.
With regards to how the club are run, previous posters are correct, the different levels of the academy all play in a similar way, formation and style, specifically to make the transition to the senior side that much smoother, allowing the academy players step up with far less risk. That is why Southampton can blood more youth players, they already know the formation and have been playing it for years (just before they actually step up they will have been training with the first team for a while).
Also correct is the fact that the first team manager of Southampton is expected to play with a certain style, to fit in with the ethos and how the club and have been training its players. The whole point being that you can lose managers, players, experience, etc. but you always have the attacking style and players experienced in it, because every part of the club is geared to that and the individual can be replaced but the system continues.
We are proud of the academy of course (there are a number of satellite academies as well), what is not mentioned so much is the scouting. The scouting network is huge, there is an enormous amount of staff whose jobs are just to collate all the videos collected / taken of players. That was also mentioned by the board in the summer (but not in any of the papers), replacements are identified for when we lose players, with video files on their play. Especially ones that should fit in with our system. Their are occasional aberrations, i.e. Pochettino insisting on Osvaldo, Cortese seeming to adore Ramirez, but generally the scouting network is trusted to identify and bring in the replacements, to minimize the risk. Koeman insisted we sign Pelle I believe, which seems to have worked out quite well as well.
Anyway, to conclude, consistent training in Strategy and style through the academy ages making it far easier for players to step up and into the first team, good facilities, not relying on individuals but trusting in the system (i.e. the manager can be replaced but the general style of play continues, obviously there is some room for the manager to make some adjustments), and a huge and detailed scouting network that has already identified replacements but generally trawls and has videos on players in matches all over the world, at all levels. The first 11 are just a tiny part of the club, but they are the ones that people usually see. Having said all that, had the owner just walked away after all the sales and took the money with her, we would have been in trouble, so there is always a weakness, no matter how much infrastructure there is behind the scenes.
Hopefully I have not bored you, sorry for posting on your forum but it is in relation to the thread and I hopefully it has filled in a few gaps in knowledge of how Southampton are run. It is still early in the season, obviously happy that we are second in the league, but a long way to go.