I said earlier you rotate 5 players then they play 22 league games each. And the likelihood is that Guardiola will play his strongest team more often, especially in the big games, meaning that a couple of players will get marginalised. You chose Real Madrid because they are the only team who operate similarly but then they dominate Spanish football, and they are more or less a permanent fixture in the last 4 of the Champions league if not the final.
This is cloud cuckoo land. I can accept that we are looking at Sanchez, but be honest enough to admit that if we do get into a position to sign him, it will mean a player leaving.
The question you have to ask though, regardless of rotation and game time, is would Sanchez make us a better team?
And the answer is of course he would. He is absolutely world class, and with world class talents like that you MAKE room.
It's similar to the argument about Van Persie all those years ago when he left Arsenal. Mancini was desperate for him despite the fact he already had 4 top quality strikers. Why? Because he would improve us. Hell, he won the rags the league single handedly.
Quite frankly, I see Sanchez's impact as the same. Could we live without him? Yes. But buying him takes us up another level.
If someone offered us Messi, would we say no based on the fact we don't need him? Would we say no because we want to bring Patrick Roberts through? No way.
Yes, the difference between Sanchez and Messi is huge. Messi isn't even world class, he is out of this world. Sanchez however is in the bracket below. He contributed to more goals in the league last year than anyone else and any team could do with that.
In response to someone needing to leave, I don't think so. In wide positions, last year we pretty much played Sane and Sterling from January onwards in pretty much every game. Brought in with Bernardo Silva and we then have 4 players for the two wide positions. Sane and Sterling are young, and at times will need to come out of the team.
I'm not saying it would keep everyone happy, but when someone like Sanchez says he is available, you make space.