I might be wrong (it's a long time since I did my driving test) but don't you have to read number plate from 30 yards or something? I certainly don't remember my examiner asking me after a 30-mile drive if I could see ok.....
If it wasn't such a pathetic excuse, you could possibly laugh. The probable truth was it was his wife's birthday and as they were feeling a bit better, whilst observing the social distancing rules, he drove her to a local beauty spot to get some fresh air and a change of scenery purely as a treat.
He couldn't say they'd gone there as a birthday treat as it wasn't essential travel and you weren't supposed to travel any distance to get exercise.