In message , Joe Egginton
writes
If crossposting is frown upon, why is it possible? Did a troll invent
the crossposting mechanism?

There are occasions when crossposting is justifiable, because a post is
genuinely on-topic for two or more groups. An example might be the
effect of the weather on railway operations in the winter of 1946-7,
which might be of interest to readers of uk.railway as well as this
group. But such instances are rare.
--
John Hall Weep not for little Leonie
Abducted by a French Marquis!
Though loss of honour was a wrench
Just think how it's improved her French. Harry Graham (1874-1936)