How HMS Rodney found unexpected speed

What was the story behind HMS Rodney supposedly finding an accelerator pedal?

Under Daryl Hamilton, Rodney was reportedly driven from a nominal 21-22 knots to roughly 25-26 knots, surprising the Germans despite stressed machinery.

Daryl Hamilton reportedly pressed HMS Rodney hard enough to surprise German observers. The approximate figures describe a 21- or 22-knot battleship reaching roughly 25 or 26 knots, even with machinery already under strain. The 'accelerator pedal' language is a humorous description of that emergency performance. The account distinguishes a warship's nominal speed from what engineering and command might extract under pressure.