He was very HIP.
Historically Informed Performance (HIP) is an approach to the performance of Western music and theater. Within this approach, the performance adheres to state-of-the-art knowledge of the aesthetic criteria of the period in which the music or theatre work was conceived. Whenever this knowledge conflicts with current aesthetic criteria, the option of re-training the listener/viewer, as opposed to adapting the work, is normally followed. Music is usually played on instruments corresponding to the period of the piece being played, such as period instruments for early music.
I think HIP is fascinating but at the same time I could agree with much of Tarushkin's criticism of it. I know very little about music though.