Tchaikovsky saw Arthur Nikisch (1855-1922) in Leipzig in 1888.
He described him as short, very pale, and "a conductor of genius" who exerted "mesmeric powers" over the orchestra.
In 1896 in St.Petersburg, Nikisch led a revelatory performance of Tchaikovsky's Fifth.
@RAMoulds I second that: the minute one needs to go into endless explanations of a piece so that it gets "understood", I feel there's something wrong with the piece itself. Or, with the trust in the audience to create their own story out of it