Leninism version is the same as Marxism. The reason Marx urged for DotP is because the capitalist will not want to lose his status or money, and will use any necessary power to restore his glory. This case has been proven, especially with the CIA. Once you entered the bougeoise government, you can only reforms capitalism & will not reach socialism. The banning of strike, the regulation of union, etc. has been shown why it is necessary to implement DotP to replace captialism. For the last part, in 19th & very early 20th century, the dictatorship mean total power. However, for some reasons the meaning has changed along to modern version. This modern definition since had lead to many misunderstanding with Marx and Lenin what meant. Even the Communist Manifesto has become a entirely different thing to the proletariat rather than we meant. If you look at Fox News, they use the word "Marxist Czar." This has shown that bourgeoise are capable of changing the defintion to suit their case.
Dictatorships mean full power, thus dictatorship of the proletarians mean the working class has full power and not the capitalist. You are quite confusing it with today definition than the ancient different definition.
