give a bunch of experts the claims in the patent and not how the patent implements the claim.
If the experts can find a way to implement the claim in a relatively short period, then the claim is obvious and should be rejected.
Of course it is possible that a more specific claim is not obvisous. For example, if there are specific performance requirements. If the initial claims are obvisious, the inventor can try again with more narrow claims.
Another requirement that is sorely needed is that an expert in the field can actually understand the patent in a reasonable period of time.