The harmonised colours will actually cause some price drops by introducing economies of scale too. Although it seems the various different fixed wiring specs, including odd-ball British and Irish standards will remain in force even if the colours of the cores change.
We may have the same colours and measure in mm but if you tried installing UK twin and earth with the undersized ground wire in most of Europe you'd be in trouble. regardless of wheather it's safe / practical or not it's a very odd standard by european norms.
I have never particularly liked the use of the very thin earth. Although, with RCD protection it's enough to cause a trip.
Where an MCB or Fuse is the only protection, I think the ground / earth cable HAS to be large enough to handle the current rated on the breaker. Otherwise, you've a potential fire and shock hazard.
I am very much in favour of ground conductors equally sized with the phase conductors.
I mean, look at the design of british plugs.. HUGE ground pin connected to this weedy little cable ... makes no sense!
