Can he rely on Gundogan this season? No. Will he still be here next? Yes. Will he be eased back into the first team? Yes. Might he be on the bench a couple of times, even after playing 90 minutes to ensure he's fully fit (and match fit) of course.
Same thing for Vincent. He's just come back from an injury that he's broken down from time and time again. He made it through 90 minutes but that doesn't mean he's suddenly fully fit or match fit.
You seem to think that in modern day football it's a case of being a) fit or b) unfit. That's absurd. Vincent was deemed fit enough to start against Palace and most were surprised he played for as long as he did in his first game back but he coped with the pace of the game easily. Not one of us would have then expected him to start against West Ham. Many thought he might be back for Swansea, but it's not really a surprise he wasn't. Why have him on the bench? For the simple reason he's Vincent Kompany. He's the club captain that's overseen our successful times and he's a leader. I saw genuine improvement defensively against Palace and West Ham. Stones looked like a man who thought, if I cock up again I'm out. Kompany's presence put a rocket up him. Phil Foden made the bench once. Was he going to play? No. But did was it still worthwhile? Of course. It exposes him to a matchday squad and that’s a good experience and gives him the hunger to get on the pitch next time.
3 games in 8 days wasn’t going to happen, even 2 was unlikely. He’ll be eased back into things to ensure his fitness. Pep wants Vincent Kompany to be fit. A fit Vincent Kompany is reliable. More so than our other options by a country mile.
He’s not going to risk him having another injury and he’ll want him fit. No point risking him Pellegrini style for a game we should be winning without him anyway. We want him fully fit for a long time. With him fit I can see us going unbeaten to the end of the season. He steps up when he needs to, he pressures the defender without diving in when the situation arises and he’s comfortable on the ball. The whole team, and crowd, lifts when he’s on the pitch. Pep wants reliable players of course, so he’s giving Kompany time to get back to full fitness and match fitness. If he breaks down again then that’s life. But you can rest assured Pep rates him more highly than any other defender at the club, as we all do.