This book is highly abstract, it can often be quite easy to get lost in Steedman's abstractions. As a result, a reread of some pages may be necessary. All in all this book can be seen as a more Heterodox approach towards the economic phenomena in which Marx proposes. Although Sraffa's critique of Marx brings with it significant changes to the way we view Marxian economics, it is not a complete rejection of the overarching edifice. If anything, Steedman poses views with challenge some notions put forth by authors such as Paul Sweezy. Steedman establishes that the rate of surplus labor is a function of the rate of profit. He operates off of the claim put forth by Michio Morishima that the rate of profit can only be positive if, and only if, surplus labor is positive. Completely rejecting the traditional notion that technological progress serves to aid the rate of profit.
Good summary of how to do sraffian analysis. Not a convincing argument that Sraffa disproves value theory or renders it obsolete.
**Edit- there's like three lines in here about international trade and how to measure labour embodied in imports that have me thinking sraffian analysis is impossible unless you have every single country's input output table...