Did Buddha explain Dependent Origination as an upaya or skillful means? If so, why? Inspired by this answer... 

Is the specific formulation of Dependent Origination in the early buddhist texts an upaya and/or skillful means?

If so, how approximate is it? Are there other conceptual elaborations that improve upon it?

If it is an upaya, what is the purpose or motivation of teaching it originally thousands of years ago? 

Is it different today?

Has our modern conception of physics and psychology led to the development of other upayas that may or may not share some of the motivation or benefits of the original?

There are parts of the early buddhist texts that include teachings on the Four Primary Elements of Earth, Water, Fire and Wind. Was this an upaya? Has modern physics provided an update to this upaya that has the same benefits as a better conceptual elaboration of the underlying truth? If not, in what way is the original better?

If you think the teaching on Four Primary Elements was an upaya or skillful means, but one that has been succeeded by a better modern version in physics and chemistry... do you think Dependent Origination is also something that could or should be updated... or one that even has been already been updated/replaced?

Thanks!
If so, how approximate is it?

If by "DO" you mean "the 12 nidanas", I found the exposition of that in the suttas barely intelligible -- little more than a dry list of the 12 items, saying that each depends on the previous.

So for that and other reasons I think of those as like chapter titles (without the text), or items on a powerpoint -- i.e. I expect they're the topic or outline of (innumerable) more-or-less detailed dhamma talks.

This site (for one) has many questions about what each nidana is and how it relates to others.

And doctrine about specific nidanas and their near neighbours, is of course important (e.g. the four noble truths).

I think though that the basic principle of DO is central and crucial -- i.e. that conditioned things arise, perpetuate, and cease depending on conditions.

If not, in what way is the original better?

I think of "earth" for example as representing "solidity".

Physics analyses that in more detail -- "why and when and how and to what extent is a substance solid?"

IIRC the context in which it's taught in Buddhism is to have some understanding of what form is -- just enough of an understanding to not get enchanted by it.