So we'll see how this one plays out, but I don't expect anything other than a mutual parting of the ways at the end of the season, when he's won us nothing, spent a fortune, and played bad football, if the next guy comes in and gets all these good players playing well then that'll be down to him, and he will deserve the credit for it.
We've been over the spending argument, his net spend of £129m or whatever it is equates to £64.5m per season, that's not a fortune for a top club just tweaking their squad nevermind rebuilding a brand new one and so i'm not sure how you can say he has spent a fortune.
And also with your final point the credit shouldn't go to any one individual, who do you credit for Barcelona's incredible successful period? Messi, Xaviesta, Guardiola? All that came before them, the board, the list goes on, they are who they are because of a lot of people.
The manager is limited in what he can do, limited by his circumstance, had Guardiola been of a different age and taken over in 1997 he would not have done what he did 10 years later.
Anyway it's up to you, if you want to look for one person who you can credit with all the glory then so be it.
Even a mutual parting of ways at the end of the season doesn't mean Louis van Gaal's work was a failure, it just means the club feel he has given them what they wanted and now they want somebody else because the circumstances are different and that somebody else will be better suited.
I think it was the Bayern CEO who said the best thing we did was sign Louis van Gaal, the second best thing we did was sack him.
The most sensible thing the board can do right now is to enter into negotiations with Mourinho's and Guardiola's representatives. And also explore installing a director of football who would be tasked with ensuring the squad is the best it can be (e.g. youth player development, transfers etc.) who would work in collaboration with the head coach tasked with winning trophies with that squad.
The board are probably doing both.