"He's done well – otherwise he gets hidings," says Bester, with a devilish grin that suggests when he sets standards, whether for his family or for his players, they should be met without hesitation.
The players of Rotherham Titans have found that to be the case since the former South African army officer returned to Clifton Lane earlier this summer for his second spell as head coach.
He left three years ago to help win custody of his son, a two-and-a-half-year battle in the courts of Belfast and South Africa he describes as the 'fight of his life'.
He departed with the club having just lost out in the Premiership promotion race to Leeds, but returns with them having spent the intervening years fighting against demotion to English rugby's third tier.
Second tier rugby has changed in the time Bester has been away, evolving from a 16-team league to a more professionally-minded 12-team division.
But nothing has changed about Bester's burning obsession to succeed, which rages as intensely as ever.
"The fact the management want me back proves that the last three years were unacceptable to them," said Bester in a manner not meant to disrespect the Craig West era, merely underlining that although his relationship with the club's board was fractious the last time he was around, his effect on the team and the club is hard to ignore.
"That's the reason why I'm back – because I've got a different mentality.
"I recruit people to play for me that have a certain mentaility, you'll see I don't say players, I recruit people. I've a group of people in the coaching staff that share my passion and my obsession of being successful at this level. This club, with it's history, should never be in a relegation play-off.
"It's an injustice to Rotherham. The club is ambitious, they want to be back in the Premiership."
Transforming a semi-professional club into title challengers alongside established full-time outfits like Bristol and Worcester is a major task, but one Bester is convinced he can achieve.
He is targeting a place in the top four – which would be an improvement of six places on last year's finish – with a bare minimum requirement for the South African being a top-eight finish and qualification for the end-of-season promotion play-offs.
His summer recruitment matches his ambitions, with a host of players having come in from Leeds Carnegie, including Jonny Hepworth, Henry Paul and his new captain Joe Bedford.
"We'll turn the club around by showing our intentions," said Bester, whose side begin the league campaign at Bristol tomorrow. "And we've shown that with the people we've brought in. But stars don't make a team, a team makes stars.
"When we were here the first year, I lost guys like Chris Hala'ufia, Scott Donald, David Strettle, Jon Goulding and Lee Blackett out of one team, and we didn't replace them and everybody said to us 'we'll be relegation fodder'. "The following season we finished second and Hendre Fourie, Jannie Bornman, Erik Lund and Joe Bedford came out of that team.
"Man-management is the important thing and for the players the key is to have faith – faith in their own abilities, faith in the set-up and the systems that are in place. We need to be honest with each other, and through honesty we build trust.
"Rugby is like warfare. I was one of the lucky ones to do conscription, I was an officer in the South African army, and I apply the same principles on the rugby pitch.
"It's about trust and being very honest, knowing that you can rely on the guy next to you when you're in the trenches.
"This league is going to be fought on an equal footing. Certain teams have an advantage because they have bigger squads of players but our advantage is that we've got resolve and an obsession within the squad of being at the top, and a belief that we should be there.
"Top four is realistic. The objective is not to be the champions, the goal is to create an environment where becoming champions is inevitible. Then we will be champions year after year."
His three-year exile from the dugout was not spent entirely in the courtroom. Bester developed equipment for the contact area called Dominant Contact which he schooled the Springboks with ahead of the British Lions tour last summer. It is now used on training pitches throughout the southern hemisphere and strengthens his belief that he returns to Clifton Lane as a better coach.
"For six months I was tormented about what went wrong, why we didn't win the Championship, all the mistakes I made," said Bester, reflecting on Rotherham's second-place finish in 2007.
"The reason I left was because of my son. Did I agree with everything the board wanted? No.
"Did they agree with everything I wanted? No.
"I've got a great relationship with the board now, we know where we all stand, we also know three, four, five years ago there were mistakes made by both sides, and I make more mistakes than anybody else because I'm more passionate than anyone and because I speak my mind."
Passionate, forthright, obsessive – woe betide anyone who does not meet Bester's standards.