Hughes was part of Sir Alex Ferguson's first two championship-winning squads and also scooped the European Cup Winners' Cup and three FA Cups with the Red Devils before joining Chelsea in 1995.
The Welshman has been battling Ferguson ever since, particularly during his Manchester City days, and is acutely aware of the fine margins between success and failure at the highest level.
And with Ferguson's successor David Moyes experiencing three defeats and two draws during his opening eight Premier League games in charge, Hughes feels the new United manager's team are teetering on the brink this term.
"You have to be careful," said Hughes, who takes his Stoke side to Old Trafford on Saturday. "There are only a certain amount of games you can lose.
"Five or six enables you to still be in the title race. Lose any more than six then you make it very difficult, nigh on impossible, for yourself.
"They have lost three and maybe they are a little bit vulnerable at the moment.
"They can't afford any more slip-ups but invariably when people question Manchester United they come back with the answers."
It has been claimed Ferguson is not making the situation any easier for Moyes by remaining in the spotlight.
Tuesday's book launch was a case in point.
It meant while acres of newsprint and TV time have been spent dissecting Ferguson's thoughts on all manner of controversial subjects, Moyes has been relegated to the role of bystander.
The echoes of 1969, when Sir Matt Busby stood down without being able to properly step away, killing any chance successor Wilf McGuinness had of being able to impose any authority, are clear.
Yet Hughes does not feel there is any chance of a repeat.
"Sir Alex would never do anything to undermine David's position," Hughes said.
"He was involved in the appointment so he's not going to do that.
"He is well aware of what's gone on before and maybe how that hindered a smooth transition.
"If he ever felt just by being there that pressure was coming to bear on David then he'd do something about it.
"But I don't anticipate that. It's just a case of them needing to settle down and move on."
Moyes did raise an eyebrow earlier in the season when he declared an intention to draw on negative experiences at both Preston and Everton to get him through the troubles he was having at Old Trafford.
Yet Hughes feels there is wisdom in that attitude.
For while the size of the clubs are so obviously different, the issues themselves are similar.
"He probably expected it to come at some point," said Hughes.
"He is stepping into the shoes of a great footballing man and it was always going to be hard.
"There will always be difficult periods in a season even if you are manager of Manchester United, who win more often than not.
"We all know he is a very experienced Premier League manager.
"He has been doing this for a long time now and anything he is facing at the moment he would have faced in the past.
"Possibly there would not be the same amount of focus but the issues are the same.
"He knows how to deal with them I am sure."
Hughes killed his own chances of squeezing into the Old Trafford hotseat when he opted to join City for an eventful 18-month stint before he was replaced by Roberto Mancini.
Now his task is to make life even harder for Moyes.
"West Brom have won there and so it's more than possible that we can get a positive result," said Hughes.
"You can't go to Old Trafford and be apprehensive. You have to be positive and have a go. If we do that let's see what happens but the expectation from ourselves and our fans is high."
Captain Ryan Shawcross, a graduate of United's academy, is struggling for Stoke, having been unwell.
Hughes is hopeful the defender will recover, but said: "Ryan Shawcross has been ill all this week.
"He didn't train on Thursday and we will need to check him in the morning. I am reasonably confident that he will come through but we do have alternatives."
Hughes has confirmed he is open to the idea of American Brek Shea leaving the Britannia Stadium on loan.
Shea was signed from Houston Dynamo by former Stoke manager Tony Pulis in January but has failed to make an impact under Hughes.
That has led to the 23-year-old expressing concerns about his hopes of making Jurgen Klinsmann's World Cup squad.
"My priority is not to get him into the USA World Cup squad. I want to get him ready to play Premier League games here," said Hughes.
"We will look at the situation and if we feel an opportunity presents itself for Brek to go out on loan and play games at a decent club and it would benefit us, we will look at it."