calling something the dog's bollocks originally meant it was obvious, ie. sticks out like a sore thumb or the testicles of a hound.
it is only recently (well, 1980s) that it has come to mean good.
( sleepybinky, Wed 22 Jun 2011, 9:10, archived)

your joke still works though, doccy P

( sleepybinky, Wed 22 Jun 2011, 9:13, archived)

So if dog testicles are made of thumbs how come they didn't evolve into hands?
Looks like your precious science doesn't have ALL the answers.
( Dr Preference AjcuiVd289, Wed 22 Jun 2011, 9:13, archived)

into hands, YET.
jeez. give them time.
( sleepybinky, Wed 22 Jun 2011, 9:14, archived)

i heard it was something to do with lego. or is that just a myth?

( manolith hooray for me, Wed 22 Jun 2011, 9:14, archived)

no, that's a female moth.

( sleepybinky, Wed 22 Jun 2011, 9:14, archived)

According to Jeremy Paxman it's an old printers' term.
Are you calling Paxman a cunt?
( Dr Preference AjcuiVd289, Wed 22 Jun 2011, 9:16, archived)

sure, why not
www.phrases.org.uk/meanings/dog's%20bollocks.html (this one supports what binky said and what you said)
www.phrases.org.uk/bulletin_board/43/messages/1022.html (this one debunks what i said)
( manolith hooray for me, Wed 22 Jun 2011, 9:25, archived)

it's a good myth, though.

( sleepybinky, Wed 22 Jun 2011, 9:47, archived)

female moths all look the same to me

( manolith hooray for me, Wed 22 Jun 2011, 9:53, archived)