> That kind of incremental improvement strikes me as the sort of thing that shouldn't be patentable.
It is. Almost all patented inventions are improvements of other inventions. Foundational new technologies are a rare exception.
> Can you really patent "changing the physical dimensions a bit so it fits better"?
It depends. If the claimed dimensions were new and non-obvious, then maybe. The obviousness analysis would depend on the particular facts of the case and could be quite complex. The questions would probably be ones like, “Would a person having ordinary skill in the art be able to discover the claimed dimensions without undue experimentation?” or “Do the claimed dimensions provide an unexpected result?” or “Does the prior art ‘teach away’ from selecting the claimed dimensions?” So, again, it depends.
It is. Almost all patented inventions are improvements of other inventions. Foundational new technologies are a rare exception.
> Can you really patent "changing the physical dimensions a bit so it fits better"?
It depends. If the claimed dimensions were new and non-obvious, then maybe. The obviousness analysis would depend on the particular facts of the case and could be quite complex. The questions would probably be ones like, “Would a person having ordinary skill in the art be able to discover the claimed dimensions without undue experimentation?” or “Do the claimed dimensions provide an unexpected result?” or “Does the prior art ‘teach away’ from selecting the claimed dimensions?” So, again, it depends.