> In my experience they never try very hard to determine obviousness With the proviso that things may have changed in the last 6 years when I haven't been work

> In my experience they never try very hard to determine obviousness With the proviso that things may have changed in the last 6 years when I haven't been working in patents: Your experience is not representative. While in Patent Litigation at Google, I looked at literally hundreds of prosecution histories, and an obviousness rejection figured in almost 100% of them. That's much more common that an anticipation rejection, i.e. ONE reference. And any lawyer will tell you that if they allow your application on the first try, you didn't ask for enough. If you tell us the numbers of the patents you worked on, I can look up the histories. Or you can, if you know that one weird trick :) (Actually, it's several weird tricks.)