Hookers 'subject' was airflow without the worry of the mechanics that had to go with it to keep it reliable. He could see that an improvement was possible but also had the 'maths' to prove it. His book gives a very fair view of the situation 'at the time' and the difficulties of all the companies having to ramp up production due to war time requirements. The original Whittle principle certainly worked well up to the Korean war period as the Mig15 proved. The Germans knew what was needed for future performance but of course they produced them for the wrong war.
Both Stanley Hookers and Rod Banks books are a great introduction to that 'interesting time' when someone had to decide on the limit that 4 stroke motors had with relation to a power/size/reliability limit, and any look at a sectioned Centaurus or Sabre (and associated gear train) leaves one in no doubt as to how complex they had become.
Remembering that the supercharger complexity had also grown accordingly and was as challenging as the engines themselves.