Running around a bit trying to close down isn't pressing. We press without any coordination. We don't squeeze the pitch, block passing lanes as we press, or set traps.
We never sustain it because it's aimless. Teams that are coached to press well, can do it for longer because there is coordinated press being done. Which is why Liverpool played a bunch of kids today and still pressed well because they are coached well to do it by good coaches. As opposed to whatever it is we do in training.
Counter pressing, and the forward line does it. Only the instructions are to get it as soon as possible to trigger an attack. Now if the ball passed the first wave of counter pressing, we don't press, which is fair, or you would run aimlessly as you said and waste a lot of energy. Once that happens, we drop deep and compact and let them come.
And this kind of counter pressing / dropping deep is something that most pressing teams are doing because otherwise, you are going to burn out. But yeah, just see what you want to see. For me, training or not, those things are being instructed. If you can't carry instructions correctly, the instructions are not the problem, but it needs to be addressed indeed.
For those who say we don't have any pressing and it's cranky. Those 2 games are widely documented so I am sure you can find videos and all explaining, but since it doesn't matter apparently, let me sum this up.
Game against Spurs
We played narrow, very narrow, and Lingard + Greenwood are pressing the 2 CBs. The objective was for Spurs to be forced to clear the ball wide because we were happy to see the ball go there. The analysis was that at that time, both Mouras and Son like to get inside, and their full backs have to provide width. It's a similar strategy Barcelona has used against us last year when they let Young go up by defending the other side against Rashford and Pogba. And they were not afraid of letting Young move up. Well, same thing for us. Call it whatever you want, but it's effective pressing with clear instructions that has a clear objective. We did the same against Spurs. Also, James is pretty good at tracking back when he's allowed to speed up so.
You pointed out that running around a bit trying to close isn't pressing. But it is. We were very happy to let the Spurs defense have the ball and pass to each others. The objective for us was to cut the ball supply to the midfield. As a results, Spurs played long. Those long balls were easier to deal for us. Also, there was one player in the defense line United tried to pressure, and it was Vertonghen. Usually, that pressing would give the ball back to United so it was a calculated risk.
Now when Spurs went through the press occasionally, United defense line was high and defended it, and since we were compact, it wasn't easy for Spurs to play the ball quick. In that game, you will notice the defense line is always higher than the box.
Game against City
In this game, instead of doing the same thing as against Spurs, it is clear that we decided to not press at all. The defense line here is always in the box, very very big difference. They wanted City to come up as much as possible. This is actually the game where Scott and Fred did a lot of work to protect the half space between our CBs and our full backs, and they defended against De Bruyne like that. So much, that De Bruyne, instead of trying to get into that half space as City would normally do, ended up changing side and going wide, very wide, and crossing, instead of being able to pass inside or have a chance to score.
Now in this game, that is fundamentally played differently than the Spurs game, and during defensive phases, one of our wide man, James, came into the midfield to defend in numbers. Martial was going to the right for the defensive work. When City moves the ball wide, James and AWB defend the right side, and that's when Scott goes into that half space created, tracking any of their players. Same setup on the other side with Rashford, Shaw and Fred.
When we attack, James goes up wide on the right again. This was a strategy to exploit the fact that City had their full backs playing pretty narrow, and that use of the position gave us balls to exploit in attack. Again, despite not pressing at all, there was one player in City's defense we tried to pressure, and that was Walker. The objective was to force the ball to go left, because we wanted to get Walker to be out of position, and that would have pushed City's team forward, meaning any counter was for us to take on that side. The other objective is something we have often see with that United team. We want the ball to go on their left, or our right, because we are now very confident with AWB ability to defend. But if the whole team was defending low, AWB was instructed to defend very high and tight on their winger. So to be simple, on the right, AWB defends alone, on the left, Shaw defends with the help of other players, more conventional. From that position, what we wanted was to have the first pass to bypass any pressure and launch and attack. So our first pass needed to be executed perfectly, or the pressure would come back.
In those 2 games, we didn't face teams that like to cross, so we now know what we need to do to defend better against teams that like to cross, we need a better defender, but the ideas are there.
In mathematics, when you state a theorem, and you can find counter examples, the theorem is invalid. Or at least, it needs to be revisited. You say we have 0 training and 0 tactical understanding and no coordinated pressing. Those 2 games show that we absolutely have coordinated pressing with clear instructions designed to exploit opponents' weaknesses and our strength, by trying to get the ball to be in areas we like. I hope that stops the nonsense that our manager doesn't have a tactical understanding of the game.
Our problem is probably more related to the players and all, but the ideas are there. And yes, I dare say that it is for me a bit of mystery but I do think that players consistency is slightly different than the manager being out of depth or whatever is the new trend on Twitter.