Sounds like my doctor except for the advice on ranges! It's lifted straight from NICE guidelines and is the bald, academic approach which works if you never steer off the path of righteousness. Depending on the actual state of somebody's pancreas and co-morbidities impacting generally (like severe arthritis that make exercise difficult), it's not the worst advice I've ever heard. He's also given the means to test which is a plus for a type 2.
In honesty, after 2 years and with the means to self test (that's the biggie), I think most people should have a good idea what they can eat. Motivation and adherence is the bigger problem.
I only have a Hba1c test once a year. Nobody at my surgery mentions diabetes in the interim and they clearly trust me to take the DIY route but it wouldn't suit everyone. In truth however, if I followed this GP's advice, I'd be fine. Except I don't take the metformin. I believe regular home testing is the real indicator of control evidenced by the people on here who have had spectacular and worrying morning highs every day but still managed Hba1c's out of diabetic range. I'm not reassured by the Hba1c because to me it's what happens every day that's more important.