Mark I saw you on another forum and you pointed out some tips on this subject. I made a circular selection and put a gradient stroke on it. I then made a shape selection on that layer and command J to another layer - and the shape - in this case a star brought along the stroke of the circle layer even though it -the stroke- wasn't included in the star selection. Don't really understand this but I think it's pretty cool and opens up possibilities. Just wanted to share this and hope someone can explain why it works like this. 
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