I don't know what the green figures mean.
No, obviously it is needed.
I don't know to what you are specifically referring.
I don't know that they are expressly forbidden.
The special dispensation allowing ring circuits does not mention them so, presumably no one would do it.
However, I think you will find that the bridge, depending on where it is, significantly reduces the problem with ring balancing, especially by primarily reducing the length of the ring for close to origin sockets.
No, it isn't.
It is just a 'normal' spur only connected to one leg of the ring.
The green figures are basically how far round the ring the load is, where 0.0 is the CU, 0.5 is the mid point, and 1.0 would be back at the CU again. Clearly 0.0 and 0.5 are ideal, because the load is shared evenly between the legs, and <0.01 would be worst, because >99% of the current would flow through the shorter leg.
I think by saying things like "depending where [the bridge] is, you're emphasising the role of careful design. Agree a shorter ring is certainly better for close sockets, but in the general case, a ring intersecting with arbitrary point on a ring would need careful design (and be unnecessary).
I am specifically referring to:
I will say, every time I mention 4mm² spurs as a simple solution to connect two single sockets on a spur instead of the allowed double,
I do expect some debate regarding the regulations and electrical consequences - of which there is none.
I'm saying there are (change in balancing of the ring and therefore possibly changes needed to return the risk of overload of one of the legs)
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I do feel like we're going in circles a bit, I see your point that every circuit has to be designed and checked on its own merits. And I'm with you on the regs now.
But the only place I feel we differ is this which my diagram, although unclear, was trying to address
In this case, with the sockets on the shorter leg, it would actually better the balance as the long leg is now shorter.
My example showed that's not the case (although I now realise you pointed out that it can sometimes make things better, sometimes worse, which I realised is true) but it's not correct to say there are no electrical consequences without knowledge of the rest of the circuit.