Not exactly a full quote/expression, but my favorite Bishop Williamson experience happened many decades ago. He was presiding over a confirmation ceremony/Mass at an independent chapel "under the umbrella" of the SSPX.
At the end of the Mass, the choir began to sing the hymn "Come Holy Ghost, " as a recessional, but right after starting, they faltered, slowed down, then completely "crashed" in a sour dissonance, and everyone stopped singing. I'm not sure to this day if it was because they realized they were singing the wrong hymn and stopped, or they just couldn't sing, but the result was a moment of awkward silence.
Then Bishop Williamson broke the silence by exclaiming "NAUGHTY, NAUGHTY!" slowly, loudly, and deliberately, in the most British way imaginable. He then started singing himself, perfectly on pitch and with great power and precision that echoed throughout the church: "Holy God, we Praise Thy Name!...." at that point all the laypeople joined in, and the befuddled choir only found their places at the second verse. Even though I was young, I was impressed by the way he took command of that situation and turned it around.