Tuohy's most acclaimed contribution to broadcasting history was his early involvement with the BBC Two channel and was the first face to appear officially on BBC Two. As the result of a disastrous power failure on the opening night, news anchor Gerald Priestland was seen briefly before transmission was aborted and the official launch postponed until the day after.
Tuohy headed the successful second attempt, however, sarcastically referring to the power cut by blowing out a candle on his desk. This image has since become an iconic piece of British television, frequently shown on TV history and nostalgia programs.
Margaret Thatcher considered that an interview she had with Tuohy in the course of the 1979 general election campaign was the most hostile she ever experienced. While Tuohy was a familiar face to television viewers his interviews were direct but said not to be typically aggressive