Nobody optimizes for any particular engine. (At least they shouldn't.)
How could you when you're optimizing for the users at the other end who are searching for your products?
I see it this way: you think about the big picture...as in trying to supply the information the search engines want to show to their users who have a demand for it (a search query = a demand for a certain kind of information..imho).
However, the search engines' algorithms are still far from perfect. They have short-comings. And understanding those barriers that are in the way of connecting users with the information theyre searching for...is what I'd consider optimizing for a certain search engine, not just for the people.
For example, I remember searching for a comparison of two similar demographics (wont go in-depth, because that'd take way long) last week. I couldnt find it, ANYWHERE :-). Technically I should be able to just create a page, and as soon as the search engine indexes it everyone around the world who does the same search or a very similar one as I did...should end up arriving at my page.
Maybe (hopefully?) search will be at that level one day. But for now, I'd still have to do some link building, wait for the page to age, etc. ...to get it to rank....and that imho works differently in different search engines (though there are similarities of course).
I think if you do anything other than only creating the best possible content for a search query (building a single link to that page, even though you know it will only send you traffic that will not buy because youre from another region), you're also optimizing for the search engine, not exclusively for the user. I think of it as removing barriers or showing the search engines the way to the (hopefully) best page you've created...but I do believe that this part is optimizing for the algorithm of a particular search engine (usually Google).
Am I taking what you said too literally?
if so, SORRY!
Actually, I think we do think along the same lines. I don't see much of a point in chasing the algorithm and focussing on technical details if I want to do "whitehat SEO" (which is what Im really focussed on). I think the algorithm stuff (for the most part) only makes sense if youre doing what they call blackhat SEO.
Btw, I dont think blackhat SEO is necessarily a bad thing (depending on the page the person delivers, if its a spammy page then I think its bad). I think what some might call grayhat SEO is a lot worse - I call it playing mind games with people...
Anyway, since Ive been learning about SEO, I started out thinking it was highly technical...to realizing that "testing absolutely everything" when it comes to the algorithm might not exactly be a high ROI strategy (partially because the algorithms dont stay the same for a lifetime..).
And lately, Ive come to the conclusion that it truly is all about the big picture...stuff such as search queries being a need for information, and your content = the supply of that information. Finding such opportunities ("need for information") that arent filled yet and providing that information and then simply understanding how to show the search engines the way (which in a perfect world with perfect search engines you wouldnt have to do...but as we live in the real world its necessary) by having a decent understanding of their algorithms (not an in-depth understanding of every little detail)...
...and that understanding where search engines are headed (big picture stuff, again..) is more important than understanding algorithm details.
Actually, I always disagree (in my mind) with the people who say that you can tell soooo easily how good someone is at SEO by simply looking at their track record/past performance which supposedly shows it all. Of course thats the key piece..and...if the person has a track record of 15 years in SEO and sites they SEO'd a long while ago still rank well, I'd agree with that. However, if someone has a great track record in this field for the past 4 years, you cannot see if they're good strategic thinkers by simply looking at their track record during the past 4 years. You have no idea how future proof the sites they SEO'd are, and how they will react to algorithm updates.
I do know one person who is great at getting things done, highly productive...and I think he is smart overall, however he has a total dislike for strategic (or analytical) thinking (basically considers doing that a waste of time, which interferes with his productivity). I wouldn't be surprised if the lifetime value from his SEO campaigns are a lot lower than those from others.