E, the focus ring on a Leupold moves very easily once the locking ring comes loose for whatever reason. If that ring comes loose, I could easily see the focusing ring being moved by (say) rubbing on a pack.
The focusing ring on my Zeiss Conquest moves much, much less easily. I honestly don't think it could be moved by rubbing on a pack, even though it doesn't have a locking ring.
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To the question of the princess and the pea... heck yeah! We are arguing over gnats here most of the time. I always mention high-end audio because that's the world I lived in for a long time, and THOSE GUYS are truly nutso.
At the root of it is this: our senses function as transducers of a sort. (A transducer converts one sort of energy into another, like a speaker turning electrical energy into sound). Our senses convert outside information, be it light or sound or smell, into electrical impulses that our nervous system and brain then process.
There is many a slip twixt cup and lip in this process! First, the quality of the transducer (eyeball in this case). I know for a fact that I don't have good eyes; I have an uncorrectable astigmatism in one eye and one of those "hoo boy!" prescriptions for the other. This is the case for many of us I imagine. We have flawed eyes. The information is corrupted before it even hits our brain.
The next step is the cognitive processing of the information. In the audio world, tales abound (and I've personally experienced this) of a roomful of guys nodding their heads and saying, "yeah, that sound better! I can hear it opening up the top end!" or whatever... as an equalizer knob is turned... and then later it turns out that the EQ knob that was being turned was switched out of the circuit! Nothing was happening! But even *I*, the audio professional, would have sworn I was hearing things change when that knob was turned. It's the effect of what you THINK you are perceiving affecting the actual perception.
Because, finally, perception is a cognitive event- not some sort of repeatable scientific measurement. Preconceptions and prejudices can and do effect our ultimate perception.
NOW, having said all that, I do value my own perceptions and I do give weight to them. When I compared the Swaro and Minox "Big Eyes" the other day I was pretty careful to try like heck to make it a fair comparison. However I will admit that having my results dovetail so cleanly with what I was told to expect (perceive) is a little suspicious!
Likewise when I was able to read finer print with a Zeiss 6.5x20 than with a Leupold that same day. I'll give that some weight. I saw it with my own two eyes <g>.
But in general the massive firefights that get rolling here and elsewhere about this minutia of perception vs. that minutia of perception are not broadly relevant to the world at large. Most people are simply not tied into their senses well enough (for one thing) to even achieve that level of sensory precision.
That's my perception about the whole thing anyway!
