Reducing speed limits - will it work?

It seems that around 2 pedestrians a year die by being hit by a car in our city of umpteen million people. I would suggest we are at greater risk choking on our Weeties.
Of course reducing speed would cause fewer accidents, this is a no-brainer, but at what point do we enter padded cells so we can’t hurt ourselves or others. Just dropping speed limits cannot change behaviour by dropkick drivers or suicidal pedestrians but it does cause frustration and turns normal law abiding people into law breakers. Just ask anyone who uses the ring road with its variable speed limits.
But, there are times when reduced limits are vital, such as Acland Street in St Kilda which needs to be 30km/h because mobile phone infused people just wander aimlessly across the road playing chicken with cars.
We drive through the city every night about 11pm between Fitzroy and St Kilda. Every night we see multiple cars run red lights. Every night we see idiot pedestrians run the suicide gamut across the traffic ignoring the fact that a ton of metal tootling down the street will turn them into a strawberry blob. ‘She’ll be right mate, I’ve only had a couple of drinks, a few drugs and my lobotomy scars have almost healed.’
Just last night we came across two girls giggling their way across the traffic whilst bemused drivers tried to avoid stiletto damage.
Sometimes I think our gene pool is too conflicted.