Earlier quoted context omitted.
Earths are to be connected to a single point, not multiple terminals of a Wago block or similar, in the UK at least. Twisting is not afaik a requirement, but it's common, and adds to the security of it. (At least, as long as the solid core hasn't been twisted and untwisted repeatedly and near the point of breaking.) OP appears to be doing it to make a fatter gauge cable out of smaller ones though?
You mean that the earth cable should run uninterrupted as a single wire from the connector of the device to the power cabinet?
- twin core & Earth line
- twin core & Earth to next fitting (or back to cabinet to complete the ring)
- live to switch & switched live return
- flex live & neutral (+ Earth if not double insulated) to light fitting
I believe it's thought that it reduces the chance of failure - one connection to check vs. a terminal block of three 'connections' where it's easy with solid core to think that they're secure when actually the middle one isn't, it's just roughly prevented from slipping out by the stiffness of the others, and potentially isn't a good electrical connection.