Felly sgrifennodd :
It may be unscientific, but it does happen, regularly, you just have to
like cricket to notice it.

It's not necessarily unscientific, it's just that science hasn't explained
it yet. There's a scientific explanation of swing at
http://www.soest.hawaii.edu/GG/STUDE...ter/swing.html
where the author concedes that:
blockquote
Despite being widely observed in practice, there is currently no theoretical,
or experimental, evidence for humidity having any affect on the amount of
swing.
/blockquote
(note the first six words).

It will be explained, eventually.

Adrian
--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.
http://users.aber.ac.uk/ais uk