One of the statutory duties of local authorities under the traffic management act is to manage the network effectively and ensure resilience. This can be done through managing traffic on the main road network and a number of key junctions or gateways into towns or cities.

It can't be done if people are able to drive wherever they like in residential areas, rat running to avoid these key control points. When this happens you lose control of everything. You can no longer manage the network as it doesn't exist except on paper or GIS

To suggest allowing through traffic should be able to use all these additional routes to meet demand is the best example of the loosening your belt to fight obesity analogy I've seen in a while.

One of the key benefits of low traffic neighborhoods is that introducing them and restricting through traffic to main roads means it can actually be managed which is the complete opposite of most uk towns and cities today

Of course they need to be implemented in parallel with measures to make main roads safer and allocate space in a fairer way not to mention the need to reduce traffic levels on them and improve air quality.

But again this can only be done if people can't cut in at the junction after the lights and stop only double yellows whole they grab a takeaway

By design traffic levels on main roads will likely increase immediately after implementation. That shows the level of the problem before and gives you the ability to manage it and make positive change. This means you can make sure one mode doesn't dominate and outgrow it's space