There could be a problem getting four 2.5mm² conductors into a socket's terminal but, as often discussed, there is otherwise no inherent problem with taking two spurs from the same socket on a ring.Yes, but only one from each socket, ...
Well, with the above caveat about terminal capacity (and a bit 'worse' {than with a 2.5mm² ring} with at least some 4mm² conductors involved).A 4mm² radial would have allowed unlimited extension in any configuration.

Or extended with 4 milli.No it doesn’t work like that.
Guessing. If he has done it in the normal way, he should have changed the fuse mcb to be less than 30A
... or, by doing what he's done and creating a 'pointless' 2.5mm² ring. As I've written to EFLI, in some senses 'pointless' if one has 4mm² cable to hand, but (if one doesn't) it does allow the use of a 30/32A OPD with 2.5mm² cable and, furthermore, if one is contemplating branches/spurs in the circuit ('now', or in the future), then one will get the number of required conductors into terminals more easily (if at all!) if none of them is 4mm²!Or extended with 4 milli.
No there couldn't.There could be a problem getting four 2.5mm² conductors into a socket's terminal
Ok.but, as often discussed, there is otherwise no inherent problem with taking two spurs from the same socket on a ring.
Well, with the above caveat about terminal capacity (and a bit 'worse' {than with a 2.5mm² ring} with at least some 4mm² conductors involved).
Other than at the last socket, the sockets on a radial circuit have two cables to start with, so that a single 'spur'/branch adds a third. Any configuration which involved more than one spur/branch from a particular socket would therefore again require at least 4 cables (i.e. 4 conductors per terminal) - and given that at least two of them would be 4mm², that would be stretching the terminal capacity even more than with a 2.5mm² ring.
I think that's a fairly sweeping statement - some people seem to 'have a problem' even putting three 2.5mm² conductors into a some sockets' terminals, and there certainly appears to be some variation between makes of socket as regards their terminal capacity.No there couldn't.
Why so?Oh dear.
No. I just thought you were waffling unnecessarily.Why so?
Are you concerned because I have mentioned one issue which, if (for whatever reason) once want's a 'branched' circuit configuration, could mean that a 'pointless 2.5mm² ring' might offer some advantages (in addition to 'CPC redundancy') over a 4mm² radial?
Oh, I see - fair enough.No. I just thought you were waffling unnecessarily.
Not really, and particularly not something designed as a cooker circuit. Don't forget that the points I raised related to the ability of BS1363 socket terminals to accommodate multiple conductors. The 'ring', per se, is not the issue - it's the difference between size of 2.5mm² and 4mm² conductors (and/or the capacity of BS1363 socket terminals) which is the issue.Then we should wire everything in rings - including the original cooker circuit.
They generally don't and, no, they don't 'need' to - which is why I only added that 'in passing', in addition to my primary point.No one considers "CPC redundancy" when installing circuits; nor do they have to.
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