Snakey character question

[Prarie Bowyer]

I'm looking at all these character and snakey bows and I'm wondering.  What determines the snakey?  I get it that the back character is determined by the growth ring and pimples and such.  But I see some that have all that and are straight on the sides and some are all squiggly.  I figured it was a grain thing also but I just saw a yew bow here with pin knots on the edge of the bow.

Can they just be arbitrarily trimmed straight?

[osage outlaw]

They follow the grain.  If you split out a stave that snakes back and forth down the length of it, that is the shape the bow will have.  If you were to cut a straight bow out of a snakey piece, it would violate the grain and make it much weaker.  Imagine a bunch of wet spaghetti noodles layed out flat on the counter top in an "S" shape.  If you cut a straight section out of the middle, how many noodles would you cut through?  How many would remain intact for the length of it?  I'm not sure if that makes any sense, but it does to me.  Now I'm craving spaghetti 

[Will H]

Thats a good way to decribe it Outlaw    The wood determines the shape. The trick to following the grain is lighting, get the light right where you can see the grain and follow it carfully for your centerline. Then just lay the bow out as you normally would in refrence to centerline. The real trick is learning how to tiller snakey bows. They can really play tricks with your eyes