The procedure does seem somewhat illogical and possibly potentially hazardous, I would be the first to say. If you feel strongly - or if there is a mismatch with unit OJTIs - why not direct the effort to CAA, either directly or through CHIRP? Do something about it!
Because I am perfectly happy with One Thousand. Never experienced a wrong read back with it. On the other hand, the form "One Zero Zero X" or "One Zero One X" does occasionally get wrong readbacks.
In this case, the One Thousand works and appears to be safe, so I am more than happy with the way I was taught by my live OJTIs rather than Hurn.
If the way I was taught is not conforming with the CAP, then I believe it's the LCEs or Training Managers' job to raise the issue, not mine.
At Hurn we used one zero zero zero, but at the college you don't experience wrong readbacks (unless they are deliberate) because the virtual pilots read the QNH off the met screen, rather than reding back the R/T in most cases.
And yes you are right, it's getting tedious. But most pprune threads become like that
