Bigger, better clubs don't experience poor spells? Man City lost something like 3 league games in 4 this past season while Liverpool blew a 7-point lead at the top (or whatever it was) by drawing 4 games in 6. Similar poor spells were also seen with Bayern, Juventus, Barcelona...
Funny you mentioned Bielsa because his teams are known to start well and then fall off the cliff, which was what happened with Leeds and look at them imploding against Derby as well...
Am fine with Allegri.
As I said to Mana, having another season of Sarri would be like signing a death warrant, especially if the transfer ban sticks!
If we can't sign anyone this summer, what makes you think we won't use our youth players a little bit more? Do you really want to see the manager flog the senior players to death again? Sarri, Lampard or whoever might be the manager can't build for the long term if they don't develop the young players.