Road Safety?

I am not a road safety consultant and do not profess to know anything about the subject so the reason for this article is to express my personal thoughts and ask if anyone who is in this field of expertise such as RoSPA or equivalent could answer some of the questions i have below.

Being a regular commuter driving the length and breath of the UK i have seen over the years a huge increase in journey times, congestion, accidents, road works all leading to a lot more time spent in the vehicle instead of doing my job.

Question A - Do smart motorways work? Personally i feel that they have been the main contributor to more serious accidents on motorways due to vehicles which have broken down being stranded in 'live' lanes instead of refuge lane e.g hard shoulder which now don't exist.

I do not know the statistics but has this lead to more collisions where heavy goods vehicles or other vehicles have ran in to the back of stranded vehicles? Also as a contributing factor i believe that due to the stranded vehicles on 'live' lanes or, resulting collisions this has lead to motorways being closed off either a number of lanes or totally for a few hours whilst the fantastic emergency services are left to clean up the carnage created by the design of the motorway infrastructure.

Question B - Why is the majority of motorway driving now 50MPH? Just before Christmas i drove from Stoke-On-Trent M6 Junction 15 to Dartford and worked out that throughout the entire journey there was probably about 20 miles where there wasn't a 50-MPH speed restriction due to miles of roadworks where no work was being carried out, or air pollution checks, or, due to congestion up ahead.

I fully understand the need for speed restrictions through roadworks due to narrower lanes but, where has the need for air pollution checks suddenly come from if more people are driving hybrid vehicles?

Also, i cannot understand how reducing the speed of traffic to 50, 40 or even 30 MPH on a motorway due to congestion up ahead stops congestion. My logic in this is surely if the traffic is being reduced at this point for the congestion ahead then won't the congestion back up behind where those who are still in the faster flow of traffic will be joining the back of the slower traffic.

I would like to highlight that i am not rubbishing safety on roads or anywhere as i am a safety practitioner and know we need systems and procedures to keep people safe but i am struggling with some of the logic behind the areas i have identified in this article and would welcome expert answers.

A - Have smart motorways reduced accidents, fatalities on the motorways?

B - Have smart motorways reduced traffic congestion?

C - Have smart motorways reduced pollution?