I guess a big bump will cause huge damage with or without the guard - I doubt the guard will contribute to additional damage in the event of 'el gordo'. However, the balance of probabilities is that the guard will protect against 99% of events which would otherwise damage the engine....
& I suppose that the engine-mounted guard will soften any blow by moving the engine on its mounts.
The force needed to move the weight of the whole car on a chassis mount would be several times greater.
Will
