Looking on it, I don't think these old Utd boys who spent most of their careers under SAF really would be the best managers.
Firstly they've spent most (if not all) of the career under one man, and no matter even if he was arguably the GOAT of managers, it still doesn't mean he can impasse his midas touch onto others. SAF's major strength was his personality and his man management and tactics wasn't really his strong point (that was left to Querioz). I think it's hard to teach someone that god-like level of man management unless telepathy can be developed and you can channel SAF into yourself... and because everyone is unique in some way, you can't just do one thing you saw once because it may not work on similar people.
Name one SAF disciple whose gone onto to have even a fraction of SAF's career at managerial level. Giggs is struggling with Wales. Scholes wasn't great for Oldham. Gary Neville was famously bad with Valencia
Completely agree with this sentiment. More to the point, it's not necessarily that they make poor managers because of Sir Alex's influence, but excellence isn't so easily transmitted.
Honestly, people lazily attach and assign credibility to certain players and managers just by virtue of proximity to
other greats. Osmosis only goes so far because despite being exposed to years of tutelage, mentorship, philosophy, and style, there are so many other aspects at play that makes a successful individual (like Sir Alex Ferguson) a
successful individual.
It would be an understatement to claim that it's extremely difficulty to transfer and replicate someone's core essence as a person and a professional onto someone else. A lot of prodigies and geniuses are indeed inspired by others that came before them (or their contemporaries), but they still have to have that inherent talent within them. They possess authentic intangibles that creates that divide between the average, the good, and the great. It's tacit knowledge.
Speaking of tacit knowledge, there's a great quote by skateboarding legend, Rodney Mullen, about this very subject.
"Dude, you just know what authentic is. That's the very nature of authenticity; tacit knowledge. Something we all know, but we can't teach. The smallest nuance of facial expressions, you know what they're thinking. Likewise with authenticity, and that is the undergirding power, like an electromotive force that pushes out style. Past that, you can't really capture it. By the time you've defined it and quarantined it to some verbal parameters (ie "the United way"), you've already missed the point."