the door beams are only so big, and they aren't going to be totally rigid. in a higher severity collision, the impacting vehicle would have engaged the door sills and lower cross-beams in the floor and that would have started to take and distribute the load. the door beams are hollow tubes....i understand concern that they bent, but thats actually what you want. if you make a car so strong that it doesn't crush and bend, the accelerations will be high and dangerous. there are so many trade-offs. that said, the S2000 is a very structurally sound car considering its size. that, in combination with decent restraints (airbags and pretensioned belts), make it a good performer in a number of crash conditions.

 

On the other side of the coin, friend went to close to the inside of a turn in his 03 SVT Focus, all he did was hit the sides of his rims(no body contact at all) and it still deployed his driver side airbag...