No you are not doing it wrong. And it has nothing to do with which side of the
pond you are on; these things can vary from bar to bar, in the same street.
If you check the Manhattan recipes, over the Webtender Wiki;
http://wiki.webtender.com/wiki/Manhattan
You will see that there is no mention of the Cherry in any of the Manhattan
recipes; there is however a slice of lemon and a twist of lemon.
Basically, it should be down to personal taste; some like cherries, some do
not.
Cheers!
George S.
g.sinclair[at]yahoo.co.ukhttp://www.wiki.webtender.com/wiki/
"Great spirits have always encountered violent opposition from mediocre minds."
-- Albert Einstein