but you need to nail it, then you should do whatever speed it takes to make it past safely
Sorry if this is stating the obvious but you can't do "whatever" speed on a test and expect to pass.
If excessing speed is required (compared to the limit) then you need to forego the overtake as the examiners from these organisations cannot condone excessive speeding.
Of course if you go on a rideout you'll see very few people sticking to the national speed limits (otherwise known as GLF - go like f***) but plenty of people sticking to good and safe practice as you describe.