[Graham Boak]

Operationally, I'd suggest that the attack flight path needed to fire the cannon would differ considerably from that required to aim and drop the bombs. Generally, it was considered a bad idea to come back and attack a target for a second time, although being well-armoured might have influenced the pilots' opinions there. I suspect that the small bombs were used as "nuisance" weapons rather than for secondary attacks, but I agree that they would provide some operational flexibility. I doubt that they would have weight-limited the aircraft - at least in more temperate climes.