As Humeround pointed out, it depends on the accuracy of the stall warner. Your man might have been dangerous, or he might have been flying within the known performance of his machine.
I fly all my circuits/turns at stall speed plus about 20-30 knots. I'm very keen to make sure all my turns have so much extra speed that I can seriously screw up my turn coordination and still not spin the aeroplane. I can always slow it down with flap and/or side slip on the final approach.
Other pilot's methods may vary and still be safe, but I'll always fly fast when low as you only need to get it wrong once.