If the national grid is so good at coping, why do we need to import electric? Why do we pay for the wind farms to shut down when there is too much power, why do we need to fire up moth balled power stations at great cost when we do not have any sun or wind for several days?
let me make it clear when I have referred to the "Grid" my comments have related to the wires that connect the generators to the consumers.
Using my definition, the grid has not failed in any significant manner simply due to the use of EV's or Heat Pumps which has been one of your principle arguments over many threads, But in fact there has not been any significant grid failure in relation to any form of new load. That is because the grid has and continues to use planned evolution to stay in step with projected demand.
There have been far bigger issues with the grid such as outages caused by extreme weather, which was also why some wind farms were turned off, because of the danger of the excessive winds damaging them.
Lack of generating plant, and the cost of electricity is the fault successive political parties inability to have a well planned energy policy, not the grids fault.
The fact is the contribution cost of construction and operating of wind and solar is so much lower than generation by burning fossil fuels or even nuclear, that has prevented your electricity bills being even bigger than they are.
By your own admission the electricity supply is complex business and one that you don't apparently understand, otherwise you would know about retaining diversity of supply, and keeping some generation facilities on hold (e.g. Moth Balled) in a state of readiness to bring on line over a period of few weeks, ready to cover for options that need maintenance or refurbishment. the cost of mothballing and reinstating is a small cost compared to having to plan, get approvals for building , spending years to construct having cost overruns and delays to create a new generating plant.