Roy Greenslade's history of British newspapers from the end of WW2 to 2004 gives a useful broad overview of the trends and characters of this industry as it reached its circulation heights and then when it started on what appears to be its irreversible decline.
If you want to know who succeeded who in the editor's or owner's chair, how old they were when appointed and even what school they went to, then this may be the book for you.
But these short, or very short, portraits by Greenslade (often of people he knew) are often marked by unsupported one word summaries of his targets (more often than not dismissive) rather than attempting to analyse what he thinks they may have got wrong (and right).
This short-cut and personality-based approach, in a very long book, makes it unfortunately read like a long shaggy dog story, with an endless conveyer belt of characters and briefly addressed incidents that you forget as you turn the page, and which is incapable of reaching a conclusion or any deep insight into why these papers rose and now fall.
'Press Gang' would need lots more detail to make it a useful history - an analysis of contents in different papers at the same time or in individual titles over time; some graphs showing circulations; details of newspaper costs in real terms or other features to give it the depth that this former tabloid newspaper editor fails to deliver.