That is a pretty diode! I just wish it was smaller than a spike
Compare figure 3 of that diode's datasheet against the figure on the 40Amp circuit breaker's
datasheet. A 400Amp surge would blow the breaker in 30 to 60 milliseconds, and is on the edge of what the diode can handle.
For even more fun, take a look at the 120A circuit breaker's datasheet. At 600 Amps, it guarantees to blow within 3 seconds.