In 2003, Jacob Aagaard published the article "Mark Dvoretsky – The Best Chess Writer in the World?" on the ChessCafe website. It was formally a review of the first English edition of Dvoretsky’s Endgame Manual, but Aagaard also discusses the series in which Technique for the Tournament Player was published. The rights to this series was later were later acquired by the Swiss publisher Edition Olms, which started publishing updated version of the books in a series now titled " The School of Chess Excellence". Aagaard does not say which volume in the new series is the updated version or replacement for Technique for the Tournament Player but he says that the level of the series "is for players of Elo 2000 and up and in reality mainly for players trying to get an international title".
Based on this, I assume that the original series by Batsford was also intended for players rated 2000 or higher.
One of the books co-authored by Mark Dvoretsky and Artur Yusupov is Technique for the Tournament Player; the English translation by Steven Lovell was published by Batsford in 1995. Apparently, it is based on training material for "gifted young chess players" and the third part of what would be a five-part series.
"Young" is rather vague, especially when you look at the young age at which some players have reached grandmaster level. (In the 1990s, when the book was published, Judit Polgár became a grandmaster at the age of 15 years and 4 moths, and Péter Lékó at the age of 14 years and 4 months.)
Does anybody know at what rating range this book is appropriate?