Earlier quoted context omitted.
Sure, determining past obviousness can be hard. That's why you bring an expert or many experts to attest to how obvious the technique is. But you don't need an expert for novelty. Either you can show a prior art or you can't. I'll grant that there may be some some edge cases where the prior art needs some nuanced interpretation from an expert witness.
I think we agree :-). I was thinking of the more subtle version of novelty which is perhaps best expressed as, "as requested". Here is a fictional example of what I'm thinking about. Lets say someone asks you to make a mud pie[1] and put bits of lavastone in it. You make your mud pie and then you patent "system and method for creating a mud pie with lava stones." Perhaps there is no prior art because nobody asked for…
This is begging the question (in the original sense of the phrase). The process is usually not somebody saying "make me a mudpie with lava stones". It usually starts with "how do I make a more attractive mudpie?" There are countless ways of doing so. You could use marbles, leaves, different mud, different levels of consistency... But maybe using lava stones gives you the most bang for the buck. So then you are really filling a patent on "method and system for increasing mudpie attractiveness".
The infamous Amazon one-click patent can similarly be viewed that way. The patent is not really solving the problem of "how do we enable purchases with one-click?" (the solution to which is blindingly obvious) but of "how do we get people to buy more things on our online store?" Now, the path from there to "one-click buying" may also be obvious, no doubt, but it's not as obvious as the path from "how do you build one-click?" to "here's how" simply because the solution space is so much bigger.