True, but I think Alonso’s record of building an over performing team with limited means at Leverkusen rather suits where Man Utd find themselves.
Any manager that over-performs builds a lot of capital. That's the sort of thing that launched Mourinho's career. Ferguson himself beat the Old Firm with an outside team - still the last manager to do so. Ranieri was an elder stateman by the time he won the league with Leicester, but that performance greatly increased his profile, at least outside of Italy.
The problem is that a one-off title campaign with an unexpected underdog is NOT the same thing as turning around a wealthy, high-profile, but misfiring club that has big, unforgiving expectations. In fact, it's sort of the opposite scenario.