Yep, agree with that.
My issue with the whole speed debate is that we are not addressing the problem, which is driving standards. That boils down to poor driver training. We're trained to pass a test, not how to drive. There's no motorway training and no vehicle dynamics training for a start (why skid pan training isn't a mandatory part of the test is beyond me). Then there's an over all lack of attention due to an over reliance on road furniture, traffic control, sat nav, all telling us what to do and people getting used to not actually thinking for themselves when it comes to driving.
Speed is a factor, yes. It's the quick win. It's not the cause though, and continuing to only focus on speed is going to eventually become less and less effective. We should in effect, be able to drive faster on our motorways for example. That's the whole point of them, to get places as quickly and efficiently as possible. But our over all standards; driving, observation, common courtesy, etc are just not up to it.