Much as I find the topic of considering music in terms of the physics and math involved fascinating, in practice, utter precision isn't really needed and may even be less than desirable as an ideal.

Auto-tune effects can make any singer sound "perfect".  But I don't know many people who think highly of that sound, other than perhaps as a novelty effect that may fit well in certain limited contexts.  To me personally, it sounds "dead" and tedious.  No feel, no color.

As has been pointed out repeatedly, the complexities involved in getting the intonation "perfect" would be exacting to the point where I doubt it would be practical as an ideal for anyone.  Even if it were attainable, other than in the equal tempered system, there would be some debate over what precise frequency actually was the "correct" one for some notes, since what was considered correct varied a bit between periods, regions, etc. 

I have a reasonably good ear, and would tend to side with Oliver in usually being able to tell when someone is playing even a bit "out of tune".  But other than long notes sounded in unison, or passages where instruments are playing chords in unison, it will not be all that noticeable to an average listener and it does not detract from a piece of music being enjoyable to listen to. 

If you listen to almost any singer that is really good when they are singing "a capella", you may note that some of their notes are "off".  They do it intentionally because it can sound better that way, and give more feel or color where they want it.  I doubt that most of them, even the best, are actually conscious of precisely how many cycles per second the frequency of each note is while they are performing.

To redirect to the original post, I wouldn't choose either option A or B.  It is only really necessary to be sufficiently close that it sounds good in context, and I consider it overly harsh to just pigeonhole shifting a pitch, sliding or using vibrato or any other sort of embellishment as "evasions". 

If anything, I consider many of the players on this forum to be overly obsessed with their intonation.  When they play, they sound good!  I think of it as only really being something that needs a hard focus in practice if one is out so far that it does not sound good.  "Watch your intonation!" gets said in critique here almost as much as the ministrations of the "bow police".  LOL  It is an easy point to pick, because one can pretty much count on at least some spots maybe being possible to be a bit tighter on the pitch, especially with people who may not have been playing long and who haven't developed much of that "musician's ear" yet.

I feel that playing well is more a matter of sounding good and the music being enjoyable than of being "perfect". 

Maybe it is just me, but this sort of discussion always seems to have some elements of

"How dast anyone think of painting a landscape when even one tree has all those leaves that would have to be painted???"

LOL

Might be better to just play.  Keep playing.  Keep trying to make it sound a little better every time.  And then just see where we get, and even if it is never perfect, we'll at least have had a good time trying.

A baby might never learn to walk, if they stopped to consider all the physics involved. 

Music was played before there was physical understanding of it or music theory, so both of those developed from the study of music as it was played and what sounded pleasing.  As such, I personally wouldn't go so far as to consider playing before one has a perfect understanding of such things as "impoverishment".  But that is just my own point of view of course.

And you are certainly entitled to your own point of view as well.

I agree that there is no "one best way" that will work for everyone, so "To each their own."

Best wishes to you in your endeavors as well.