Yeh do well at AS kids and A2 can become a hell of a lot easier.
I got 280 for Ancient History, which is a bitch of an AS because the mark schemes basically require you to have read every ancient source possible relating to your topic, though you can get round this by reading the most important ones and stealing the opinions of people who have written summaries.
However, because I got this mark, and did well in the coursework 93/100 raw marks, even if the coursework goes down a little to 90 or so, then I need 110/200 to get an A, meaning I need to get two mid level Ds on my remaining papers. Which is easier, getting over 90% UMS at AS or getting Ds in A2 papers? I'd choose the latter any day.
Overall I'd say it is generally harder to get an A at A2, certainly is for German and Classics. However, The only point of A2 grades is in determining your total A level grade, they have no independent merit, unlike AS grades which go on yourUCAS form etc. I would far rather have very high AS grades, lower A2s and an A overall, than low AS grades, not be going to a good uni , high A2s and then an A overall.