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The gravity and forces we're talking about are tiny. The craft hit the ground moving slower than 1 m/s and then bounced up over 1km before landing again. The forces involved with something moving that slowly and stopping are minuscule.

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This is fascinating. I imagine they probably ran simulations with different margins and as a few bounces would have been one of the expected outcomes i.e. it would have been factored into the design of the craft?

The craft had a small thruster on its top side to gently push it into the surface of the comet, but this seems to have been faulty and couldn't be primed prior to Philae's separation. It sounds like the sort of equipment that might have mitigated such a bounce!

In the end, the speed at which Philae left the comet after the initial bounce was not far off reaching the escape velocity of the comet!

The thrusters and harpoons failed, and I don't think the ice screws have really had a chance.

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