I had for many years heard people rave about Simple Chess: it was the book that made them understand things they never previously had; it wasn't just for simple players, etc. I once loaned it from a library when I had just become a newly minted old ECF 100 player, and being in descriptive, and my own chess ideas barely crystallising day by day, I found it too hard-going. Fast-forward ten years when I'm knocking on the new 160. I recently started reading Reassess Your Chess, and found it thoroughly confusing for one or other reason. While I'm sure the concepts will stick in (it could be simply the first few chapters are things I don't need or are what I need strongly to rebuild upon), when I then tried Stean's algebraic edition of SC, things began to click quite nicely!
Over seven chapters (Introduction, which is far more than you'd think), Outposts; Weak Pawns, Open Files; Halfopen Files/Minority Attack, Black/White Squares; and Space, Stean, one of Britain's top players in the 70s, takes us through technical chess using well-worked examples, but without any overly dogmatic waffle as one might see from a Silman or a Nimzowitsch. Open games, and closed games feature, and within its pages are hidden nuggets of advice from a top player which apply to any games you might have; including on development, the desire for material, and a general thread throughout which touches lightly upon planning as the means to the end, but without the overarching zealousness that can be so confusing in modern chess.
To this end, the book is entirely relevant today, showing positions with particular technical features and breaking down the victories in to manageable chunks and goals, but also giving tactical points throughout. For anyone above 1550 Elo or 110 ECF, I can thoroughly recommend this deep book, especially if you have ever struggled with praxis from Silman or Kotov to name but two. Try reading them together, and watch your play improve as you know it can!
While I have not fully read the book yet, I can only see minor typographical errors (with one move in 63 pages missing, viz. subvariation move 21...Ne5 in Fischer-Petrosian game 7, in chapter 2. This does not at all detract from the fluid prose of Stean, nor his many full-game examples. Fully recommended!