Genghis - CAP 804 doesn't contradict itself, it simply combines the requirements of the ANO and Part-FCL, which is not unreasonable considering that both will be law in the UK after 17 Sep. Consequently, there will be legal obligation to comply with both the ANO requirement to record 'instrument flying' and the Part-FCL requirement to record flight under IFR.
The problem is that while the Part-FCL terms 'instrument time', 'instrument flight time' and 'instrument ground time' are all clearly defined, the ANO term 'instrument flying' is not. This is what led the CAA's Policy wonks to start the entirely counter-productive debate that Whopity alludes to regarding how much of an instrument training flight may be counted as 'instrument flight time'.