Dean Richards says three years out of rugby has taught him the difference between ambition and cheating.
The former Harlequins boss was given a worldwide ban after wing Tom Williams used a blood capsule to fake injury during a game against Leinster in 2009, allowing a goal-kicker to be brought on.
The suspension is now served and Richards will take charge of Newcastle for the forthcoming Premiership season with his will-to-win undimmed.
But he said: "I have huge regrets and I would never, ever do the same thing again.
"In terms of personality, I have the same ambitions to win things and the same passion. Nothing has changed in terms of my appetite and what I want out of the game.
"But I have huge regrets. I understand exactly where the boundaries lie and I would never step over them again.
"If people want to say something, they can say something. If they feel I should have got more of a ban, then so be it. I was given three years and I have done three years."