I was talking ref our regs BS7671 only. other countries will differ but Europeans will have many similarities with ours although still some different quirks.
Trees are, in actuallity, the same whether they are all in the fuseway or in joint boxes (including ceiling roses, they are just a more pretty variant of a joint box really) .
Some of our lot get a bit hung up thinking that whilst a tree might be OK if the first split is from a joint box yet not at the fuseway, which is not logical if you think about it but it`s the wat they`ve been brought up.
Yet others seem to think a radial must to 1,2,3,4,5 ..... to N (N being the total number) in a straight chain.
Whilst more elegant and also easier to test, it is not mandated, just in the same way that a 1 ring ring final is not mandated.
Lassoos again likewise.
Just because something is not listed in the OSG (standard circuits) or the informative appendices of BS7671 does not mean that they do not conform to the regs.