wrist action vs accuracy

[fwellers]

Hi,
I've often heard how much accuracy is affected by the different people wearing their watches differently. For me, this isn't making sense.

My limited understanding of the way mechanical watches work leads me to think that the only thing wrist action does is wind the mainspring.
The affects of the movement of your hand are blocked to the movement, except for the mainspring. The escapement translates tension on the mainspring into very precise and regulated clicks to the gears.

So this means that I can shake my hand like wild, or just walk regularly, and it means absolutely nothing to the movement except to wind it.

Now I have heard that a fully wound watch, has more tension on the mainspring, making it just a tad more presice, than an almost unwound watch.

But that being said, consider the myriad of people, who go through their day wearing the watch, keeping the mainspring fairly wound. It shouldn't matter whether one of them bowls all day, vs another who is a desk jockey, vs another who swims all day. As long as the mainspring remains on the upper end of wound, there should be zero affect on the watches accuracy or precision.

Ok, so correct my mistakes here please.

Thank you.

Floyd