It's not the CAA who give such little credit, it's the JAA. Under the old CAP 53 rules for UK PPLs, the CAA gave a lot more credit - unfortunately no-one from the ATC or BGA world challenged the ridiculous Regulatory Impact Assessment trotted out by the CAA 5 years ago (it was a total piece of fiction, in my view) - and you're now stuck with it....
But we've been able to secure far greater credit towards the NPPL - because they were agreed by industry, not by faceless paper shufflers in Europe!