Stan, I think you have the right of this.
If a farmer is planting by the signs and those signs happed to coincide with the best time of year to plant seed, there you go.
But when it comes to scheduling surgery by the signs, I'm not buying it.
Likewise using the uppermost part of a stave for the uppermost limb of the bow, I'm not taking that one either, even if it did come from a well respected bowyer.
This reminds me of a story I heard one time...
The newly married husband was watching his wife prepare a roast for the oven. When she cut a piece of meat off the end of the roast before putting it into the roasting pan he asked her why she'd done that.
"That's what my mother always did for roasts," she replied.
That got his curiosity up so he phoned his mother in law and asked her why she did that on roasts.
"That's what my mother always did for roasts," she replied.
Now he was really curious about the whole thing so he phoned the rest home where the old lady now lived and asked her the question.
"My pan was too damn small," she barked.
Sometimes there's a good reason for doing something, and sometimes there isn't.
Having said that, if it works for you, then do it and no harm nor foul.
Guy